Malicious Exchange or SharePoint Worker Process Spawning Command Shell from Web Shell (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-08-13
Updated
2026-08-28

ATT&CK techniques

Execution → Persistence
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Priv Esc

  5. Defense Evasion

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule detects the IIS worker process w3wp.exe spawning command shells or the net utility on on-premises Exchange or SharePoint servers, the web-shell execution behavior these attacks use after deploying pages such as getidtoken.aspx or signout.aspx. Adversaries drop web shells into OWA auth and LAYOUTS directories to run commands in the server context, so command interpreters descending from w3wp indicate server-side compromise.

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Malicious Exchange or SharePoint Worker Process Spawning Command Shell from Web Shell (via process_creation)
Pivot detection · T1059.001 · 9 related

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