Suspicious Python HTTP Server Started for Payload Staging After Citrix Bleed Exploitation

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects use of the Python built-in HTTP server module to host files on a local port, a hands-on-keyboard technique seen in Citrix Bleed (CVE-2023-4966) post-exploitation by Unit 42. Adversaries stand up an ad hoc web server to transfer tooling laterally which is rare on production endpoints and signals active intrusion.

Reporting behind it

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Suspicious Python HTTP Server Started for Payload Staging After Citrix Bleed Exploitation

Pivot detection · T1105 · 9 related

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