CVE-2026-61554

emp3r0r is a C2 designed by Linux users for Linux environments. Prior to version 4.2.5, the http_poll C2 transport accepts attacker-controlled HTTP polling sessions before CBOR MsgAuth authentication is completed. A remote unauthenticated attacker can create arbitrary polling sessions and send request bodies that are forwarded into the C2 dispatch path. This can consume server resources and trigger pre-auth C2 processing. Version 4.2.5 patches the issue.