Resource exhaustion in Jm33-M0 Emp3r0r

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.

Vulnerability class: DoS (Denial of Service)

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-61554?
CVE-2026-61554 is a high-severity vulnerability in Jm33-M0 Emp3r0r, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-09-15.
How severe is CVE-2026-61554?
High severity. CVSS v3 base score is 7.5 out of 10.