LoFP LoFP / authorized github actions runner with no malicious workflow actions.

Techniques

Sample rules

Execution via GitHub Actions Runner

Description

This rule detects potentially dangerous commands spawned by the GitHub Actions Runner.Worker process on self-hosted runner machines. Adversaries who gain the ability to modify or trigger workflows in a linked GitHub repository can execute arbitrary commands on the runner host. This behavior may indicate malicious or unexpected workflow activity, including code execution, file manipulation, or network exfiltration initiated through a compromised repository or unauthorized workflow.

Detection logic

process where event.type == "start" and event.action in ("exec", "exec_event", "start", "ProcessRollup2", "executed", "process_started") and
 process.parent.name in ("Runner.Worker", "Runner.Worker.exe") and
 (
   process.name like ("curl", "curl.exe", "wget", "wget.exe", "powershell.exe", "cmd.exe", "pwsh.exe", "certutil.exe", "rundll32.exe", "bash", "sh", "zsh", "tar", "rm",
                     "sed", "osascript", "chmod", "nohup", "setsid", "dash", "ash", "tcsh", "csh", "ksh", "fish", "python*", "perl*", "ruby*", "lua*", "php*", "node", "node.exe") or
   process.executable : ("/tmp/*", "/private/tmp/*", "/var/tmp/*", "/dev/shm/*", "/run/*", "/var/run/*", "?:\\Users\\*")
 )