huntrule

Suspicious Linux Process Execution From /tmp Directory

Flags execution of binaries located under /tmp on Linux, excluding a known Nextcloud path.

FreeReviewedSigma · Medium · v2
Product
linux
Category
process_creation
Author
Joseliyo Sanchez, @Joseliyo_Jstnk (SigmaHQ), DRL 1.1
Published
2023-06-02
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Defense Evasion

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags Linux process creations where the process image path starts with /tmp/, indicating the executable was launched from a temporary directory. Attackers often use /tmp to run dropped payloads or execute tools that avoid well-known install locations. The detection relies on Linux process creation telemetry that includes the executed image path.

Reporting behind it

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Suspicious Linux Process Execution From /tmp Directory
Pivot detection · T1036 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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