LoFP LoFP / there is a potential for false positives if the \"id\", \"whoami\", \"capsh\", \"getcap\", or \"lsns\" commands are used for legitimate purposes, such as debugging or troubleshooting. for example, an operator may use the \"id\" command to verify the identity of the current user, or the \"whoami\" command to verify the current user. it is important to investigate any alerts generated by this rule to determine if they are indicative of malicious activity or part of legitimate container activity.

Techniques

Sample rules

Interactive Privilege Boundary Enumeration Detected via Defend for Containers

Description

This rule detects the execution of the “id”, “whoami”, “capsh”, “getcap”, and “lsns” commands inside a container. These commands are used to enumerate the privilege boundary of the container, which can be used by an adversary to gain information about the container and the services running inside it.

Detection logic

process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and process.interactive == true and (
  (process.name in ("id", "whoami", "capsh", "getcap", "lsns")) or
  (process.args in (
     "id", "/bin/id", "/usr/bin/id", "/usr/local/bin/id",
     "whoami", "/bin/whoami", "/usr/bin/whoami", "/usr/local/bin/whoami",
     "capsh", "/bin/capsh", "/usr/bin/capsh", "/usr/local/bin/capsh",
     "getcap", "/bin/getcap", "/usr/bin/getcap", "/usr/local/bin/getcap",
     "lsns", "/bin/lsns", "/usr/bin/lsns", "/usr/local/bin/lsns"
   ) and
    /* default exclusion list to not FP on default multi-process commands */
    not process.args in (
      "man", "/bin/man", "/usr/bin/man", "/usr/local/bin/man",
      "chmod", "/bin/chmod", "/usr/bin/chmod", "/usr/local/bin/chmod",
      "chown", "/bin/chown", "/usr/bin/chown", "/usr/local/bin/chown"
    )
  )
) and container.id like "?*"