Malicious Citrix WFShell Spawning Command Interpreter via Command Line

ATT&CK techniques

Initial Access

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

What it detects

This rule detects the Citrix wfshell.exe or cmstart.exe process spawning a command interpreter, a post-exploitation chain observed after abuse of the Citrix Bleed vulnerability CVE-2023-4966 leading to LockBit ransomware. These Citrix components should not launch shells. Detecting the chain exposes hands-on-keyboard activity following gateway compromise.

Reporting behind it

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Malicious Citrix WFShell Spawning Command Interpreter via Command Line

Pivot detection · T1190 · 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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