VulnerabilityAnalyzed

CVE-2026-26068

Prior to 3.21.1, untrusted agent metadata (Transport, Hostname) is accepted during check-in and later interpolated into tmux shell command strings executed via /bin/sh -c.

CRITICAL 9.3EPSS 3.40%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (3.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

emp3r0r is a stealth-focused C2 designed by Linux users for Linux environments. Prior to 3.21.1, untrusted agent metadata (Transport, Hostname) is accepted during check-in and later interpolated into tmux shell command strings executed via /bin/sh -c. This enables command injection and remote code execution on the operator host. This vulnerability is fixed in 3.21.1.

CVSS 4.0: 9.3 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 3.40% probability · 88th percentile
CISA KEV: Not listed
Weakness: CWE-77, CWE-78
Affected: jm33-m0/emp3r0r
Source: security-advisories@github.com

References

https://github.com/jm33-m0/emp3r0r/commit/0cd64e4a26e7839a9a54bca3d756a665fcb7fda0Patch
https://github.com/jm33-m0/emp3r0r/releases/tag/v3.21.1Product, Release Notes
https://github.com/jm33-m0/emp3r0r/security/advisories/GHSA-h5p4-4xp4-vjppExploit, Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.