Vulnerability · Published Sep 15, 2026 · Assigned by GitHub_M

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

High 7.5

In plain English

A high-severity uncontrolled resource consumption in emp3r0r from jm33-m0. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 54% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.7%top 46.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/jm33-m0/emp3r0r/core	0.0.0-20260531142011-aed3d81641ab	GHSA-4595-rvpx-4q34
Go	github.com/jm33-m0/emp3r0r/core	0.0.0-20260531142011-aed3d81641ab	GO-2026-6487

Affected products (as reported)

Vendor	Product	Versions
jm33-m0	emp3r0r	< 4.2.5

Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://github.com/jm33-m0/emp3r0r/security/advisories/GHSA-4595-rvpx-4q34 x_refsource_CONFIRM
https://github.com/jm33-m0/emp3r0r/releases/tag/v4.2.5 x_refsource_MISC