CVE-2026-61554: emp3r0r has an unauthenticated HTTP Polling DoS

September 15, 2026

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.

References

github.com/advisories/GHSA-4595-rvpx-4q34
github.com/jm33-m0/emp3r0r/releases/tag/v4.2.5
github.com/jm33-m0/emp3r0r/security/advisories/GHSA-4595-rvpx-4q34
nvd.nist.gov/vuln/detail/CVE-2026-61554

Code Behaviors & Features

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