huntrule

Windows Process Watch: PythonFunctionWarnings Disabled via Excel Security Registry Setting

Flags Excel-related process command lines that disable Python function execution warnings via PythonFunctionWarnings=0.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
@Kostastsale (SigmaHQ), DRL 1.1
Published
2023-08-22
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

  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 process command lines that include a registry path and value indicating Python function execution warnings are disabled for Microsoft Excel. Suppressing these warnings can reduce visibility into Python-in-Excel activity and hinder alerting on potential malicious use. It relies on process creation telemetry containing the specific command-line fragments referencing Excel’s Security and the PythonFunctionWarnings value set to 0.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange
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Suspicious In-Memory PowerShell Execution from Web Server via Automation Assembly (via image_load)
Malicious EDR Evasion Driver Load from AnyDesk Directory via k.sys (via image_load)
Malicious Zemana Vulnerable Driver Load for EDR Termination (via image_load)
Windows Process Watch: PythonFunctionWarnings Disabled via Excel Security Registry Setting
Pivot detection · T1685 · 9 related

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