Malicious Native IIS Module Installation via Appcmd by UAT-8099

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.004IIS Components
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects registration of a native IIS module using appcmd. UAT-8099 installs malicious BadIIS modules to intercept web traffic on compromised servers. Rogue IIS modules give an actor passive persistence and traffic manipulation inside the web server process.

Reporting behind it

Related detections9 linkedT1505.004 — drag to rearrange

Malicious BadIIS Module Load into IIS Worker Process by UAT-8099

Suspicious Malicious IIS Module DLL Written to Inetsrv Directory (via file_event)

Malicious Webserver IIS Configuration Edited - SYSMON (via file_event)

Malicious Webserver IIS Module Installed - Command (via process_creation)

Malicious Webserver IIS Module Installed - Command (via process_creation) - Variant 2

Malicious Webserver IIS Module Installed - PowerShell (via powershell)

Malicious IIS Native Module Installation via Appcmd IsapiCachesModule (via process_creation)

Malicious BadIIS SEO Poisoning C2 Request via Web Server (via webserver)

Windows IIS module removal event (IIS-configuration EventID 29)

Malicious Native IIS Module Installation via Appcmd by UAT-8099

Pivot detection · T1505.004 · 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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