Suspicious IIS Worker Process Spawning Encoded PowerShell via CentreStack Exploitation

ATT&CK techniques

Initial Access → Execution

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects an IIS worker process spawning cmd or PowerShell that runs base64 encoded payloads, behavior observed during active exploitation of Gladinet CentreStack and Triofox local file inclusion flaws. Attackers leverage the web application context to achieve remote code execution and stage further tooling. Web servers rarely spawn encoded interpreters, so this indicates likely post-exploitation activity.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

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Malicious IIS Worker Process Spawning PowerShell via Gladinet CentreStack Exploit

Suspicious IIS Worker Process Spawning Encoded PowerShell via CentreStack Exploitation

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.

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