Exchange Worker Process Spawning Command Shell via OWASSRF
- Product
- windows
- Category
- process_creation
- Author
- HuntRule
- Published
- 2026-09-28
- Updated
- 2026-09-28
ATT&CK techniques
Initial Access → PersistenceRecon
Resource Dev
Initial Access
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects the IIS Exchange worker process w3wp.exe spawning cmd.exe or PowerShell, a hallmark of web-facing exploitation such as the OWASSRF Exchange remote code execution chain. Huntress observed base64-encoded PowerShell whoami commands launched this way for post-exploitation reconnaissance. Shell children of the Exchange worker almost always indicate a webshell or server-side request forgery exploit.
Reporting behind it
- huntress.comhttps://www.huntress.com/blog/threat-intel-accelerates-detection-and-response
- attack.mitre.orghttps://attack.mitre.org/techniques/T1190/
- attack.mitre.orghttps://attack.mitre.org/techniques/T1059/001/
- attack.mitre.orghttps://attack.mitre.org/techniques/T1059/003/
- securelist.comhttps://securelist.com/new-tropic-trooper-web-shell-infection/113737/
- attack.mitre.orghttps://attack.mitre.org/techniques/T1505/003/
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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