Suspicious SUID Binary Execution (Auditd Sequence)

[metadata]
creation_date = "2026/05/08"
integration = ["auditd_manager"]
maturity = "production"
updated_date = "2026/05/08"

[rule]
author = ["Elastic"]
description = """
Detects suspicious sequences where a non-root user launches a high-risk parent process (interpreter, shell one-liner, or
execution from user-writable paths) and then quickly executes a common privilege elevation helper (su, sudo, pkexec,
passwd, chsh, newgrp) that gains an effective UID of 0 while the real UID remains non-root. This can indicate misuse of
SUID/SGID helpers, polkit/sudo abuse, or interactive privilege escalation attempts captured via Auditd Manager telemetry.
"""
false_positives = [
    """
    Some break-glass workflows or automation may legitimately invoke sudo/su from scripts under user home directories.
    Validate the initiating user, parent context, and change approvals; tune by known admin tooling paths or accounts.
    """,
]
from = "now-9m"
index = ["auditbeat-*", "logs-auditd_manager.auditd-*"]
language = "eql"
license = "Elastic License v2"
name = "Suspicious SUID Binary Execution (Auditd Sequence)"
note = """## Triage and analysis

### Investigating Suspicious SUID Binary Execution (Auditd Sequence)

Confirm whether the non-root real user should be invoking su, sudo, pkexec, or account utilities as root. Review the
parent process chain and whether the parent executable location or shell invocation suggests a one-liner or staging
from user-writable paths.

### Possible investigation steps

- Review process details for script paths, temp directory execution, or suspicious interpreters.
- Check sudoers / polkit policy changes and recent authentication events for the user.
- Pivot for follow-on persistence (cron, systemd units) or credential access from the same session.

### Response and remediation

- If unauthorized, contain the session, revoke elevated access, and review sudoers and polkit configuration for tampering.
"""
references = [
    "https://attack.mitre.org/techniques/T1548/",
    "https://docs.elastic.co/integrations/auditd_manager",
]
risk_score = 47
rule_id = "50eba7ec-d3f0-474c-a7f4-0906b68e350f"
severity = "medium"
tags = [
    "Data Source: Auditd Manager",
    "Domain: Endpoint",
    "OS: Linux",
    "Use Case: Threat Detection",
    "Tactic: Privilege Escalation",
    "Resources: Investigation Guide",
]
timestamp_override = "event.ingested"
type = "eql"
query = '''
sequence by host.id with maxspan=30s
  [process where host.os.type == "linux" and event.type == "start" and
   event.action == "executed" and
   user.id != "0" and user.effective.id != "0" and
   (
     process.name like ("python*", "perl*", "ruby*", "php*", "lua*", ".*") or
     process.name in ("node", "bun", "java") or
     process.executable like ("/tmp/*", "/var/tmp/*", "/dev/shm/*", "/run/user/*", "/var/run/user/*", "/home/*/*") or
     (
       process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish", "mksh") and
       process.args in ("-c", "--command", "-ic", "-ci", "-cl", "-lc")
     )
   )
  ] by process.pid

  [process where host.os.type == "linux" and event.type == "start" and
   event.action == "executed" and
   user.effective.id == "0" and user.id != "0" and
   (
     (process.name in ("sudo", "pkexec") and
      not process.args like "-*" and
      not process.args : ("/usr/*", "/bin/*", "/sbin/*", "/opt/*")) or
     (process.name == "su" and
      not process.args in ("--command", "-c", "--shell", "-s")) or
     (process.name in ("passwd", "chsh", "newgrp") and
      not process.args in ("--shell", "-s", "--help"))
   )
  ] by process.parent.pid
'''

[[rule.threat]]
framework = "MITRE ATT&CK"

[[rule.threat.technique]]
id = "T1548"
name = "Abuse Elevation Control Mechanism"
reference = "https://attack.mitre.org/techniques/T1548/"

[[rule.threat.technique.subtechnique]]
id = "T1548.001"
name = "Setuid and Setgid"
reference = "https://attack.mitre.org/techniques/T1548/001/"

[[rule.threat.technique.subtechnique]]
id = "T1548.003"
name = "Sudo and Sudo Caching"
reference = "https://attack.mitre.org/techniques/T1548/003/"

[rule.threat.tactic]
id = "TA0004"
name = "Privilege Escalation"
reference = "https://attack.mitre.org/tactics/TA0004/"