Vulnerability · Published Feb 19, 2026 · Assigned by GitHub_M

CVE-2026-26201emp3r0r Affected by Concurrent Map Access DoS (panic/crash)

High 7.0

In plain English

A high-severity race condition in emp3r0r from jm33-m0. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)7.0High

Exploit odds (30 days)0.3%top 73.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

emp3r0r is a C2 designed by Linux users for Linux environments. Prior to version 3.21.2, multiple shared maps are accessed without consistent synchronization across goroutines. Under concurrent activity, Go runtime can trigger `fatal error: concurrent map read and map write`, causing C2 process crash (availability loss). Version 3.21.2 fixes this issue.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/jm33-m0/emp3r0r/core	0.0.0-20260212232424-ea4d074f081d	GHSA-f5p9-j34q-pwcc
Go	github.com/jm33-m0/emp3r0r/core	0.0.0-20260212232424-ea4d074f081d	GO-2026-4504

Affected products (as reported)

Vendor	Product	Versions
jm33-m0	emp3r0r	< 3.21.2

Weakness: CWE-362, CWE-663 · Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H

References

https://github.com/jm33-m0/emp3r0r/security/advisories/GHSA-f5p9-j34q-pwcc x_refsource_CONFIRM
https://github.com/jm33-m0/emp3r0r/commit/ea4d074f081dac6293f3aec38f01def5f08d5af5 x_refsource_MISC
https://github.com/jm33-m0/emp3r0r/releases/tag/v3.21.2 x_refsource_MISC