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

ATT&CK techniques

Execution → Persistence

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
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.

Reporting behind it

Related detections9 linkedT1505.003 — drag to rearrange

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

Pivot detection · T1505.003 · 9 related

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

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