huntrule

Linux Wget Writing Files Under /tmp or /var/tmp

Alerts when wget creates files under /tmp or /var/tmp on Linux.

FreeReviewedSigma · Medium · v3
Product
linux
Category
file_event
Author
Joseliyo Sanchez, @Joseliyo_Jstnk (SigmaHQ), DRL 1.1
Published
2023-06-02
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

C2

  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 matches process activity where wget is the executable and it writes/creates files with target paths starting in /tmp/ or /var/tmp/. Downloading into temporary directories is a common attacker technique for staging payloads before execution or exfiltration. It relies on Linux file event telemetry that includes the process image path/name and the destination TargetFilename.

Reporting behind it

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Linux Wget Writing Files Under /tmp or /var/tmp
Pivot detection · T1105 · 9 related

Changelog

v3
  1. v3
    Candidate ingested via manual entry.2026-07-31
  2. v2
    Candidate ingested via manual entry.2026-07-31
  3. 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.