Malicious Rogue Root User Creation via Useradd UID Zero

PremiumReviewedSigma · High · v1
Product
linux
Category
process_creation
Author
HuntRule
Published
2026-06-01
Updated
2026-08-28

ATT&CK techniques

Persistence
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects useradd invoked with the non-unique flag and a UID of 0 which creates a hidden secondary root-equivalent account for persistence and privilege escalation on Linux. Adversaries add a UID 0 account to retain full administrative control while blending in as an ordinary user.

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Malicious Rogue Root User Creation via Useradd UID Zero
Pivot detection · T1136.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.