huntrule

Windows Processes Creating PCRE.NET Temp Package Files

Identifies Windows processes writing temp files with a PCRE.NET package-specific path under AppData\Local\Temp.

FreeReviewedSigma · High · v2
Product
windows
Category
file_event
Author
Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research) (SigmaHQ), DRL 1.1
Published
2020-10-29
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Execution

  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 identifies file events where a process creates a file in the Windows user temporary directory containing a specific PCRE.NET package temp filename fragment. Attackers and installers may write transient artifacts to Temp to execute or stage components, so matching these unique temp paths can highlight suspicious local activity. It relies on file creation or file event telemetry that includes the target filename for Windows.

Reporting behind it

Related detections9 linkedT1059 — drag to rearrange
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Malicious AutoHotKey Runner AutoNotify Executing AHKBot Looper Script (via process_creation)
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Windows Processes Creating PCRE.NET Temp Package Files
Pivot detection · T1059 · 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.