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Windows Process Creation: Indicators of SharePoint spinstall0.aspx Encoded Command Exploitation (CVE-2025-53770)

Alerts on w3wp.exe command lines containing encoded spinstall0.aspx and SharePoint template layout path indicators consistent with CVE-2025-53770 exploitation.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Swachchhanda Shrawan Poudel (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2025-07-21
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Initial Access

  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 Windows process creation events where w3wp.exe launches commands containing encoded indicators tied to spinstall0.aspx and SharePoint template paths. Such activity can reflect post-exploitation behavior attempting to execute payloads through web application worker processes. The detection relies on process command-line telemetry and specific encoded strings/patterns observed in those command lines.

Reporting behind it

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Windows Process Creation: Indicators of SharePoint spinstall0.aspx Encoded Command Exploitation (CVE-2025-53770)
Pivot detection · T1190 · 9 related

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