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

Vulnerability summary

CVE-2026-26201 is a high (CVSS 7.5) vulnerability in jm33-m0 emp3r0r. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 26.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 19-02-2026
   PublishedVulnerability first disclosed.
2. 19-02-2026
   Last modifiedVulnerability information updated.

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.

• CWE-362Concurrent Execution using Shared Resource with Improper SynchronizationThe product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
• CWE-663Use of a Non-reentrant Function in a Concurrent ContextThe product calls a non-reentrant function in a concurrent context in which a competing code sequence (e.g. thread or signal handler) may have an opportunity to call the same function or otherwise influence its state.