CVE-2026-4631: Cockpit: cockpit: unauthenticated remote code execution due to ssh command-line argument injection

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 15.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-07 · updated 2026-10-26
Weakness: CWE-78

Description

Cockpit's remote login feature passes user-supplied hostnames and usernames from the web interface to the SSH client without validation or sanitization. An attacker with network access to the Cockpit web service can craft a single HTTP request to the login endpoint that injects malicious SSH options or shell commands, achieving code execution on the Cockpit host without valid credentials. The injection occurs during the authentication flow before any credential verification takes place, meaning no login is required to exploit the vulnerability.

Affected products

Red Hat Enterprise Linux 10: all versions — fixed in 0:344-3.el10_1, 0:356.1-1.el10_2
Red Hat Enterprise Linux 10.0 Extended Update Support: all versions — fixed in 0:334.1-3.el10_0
Red Hat Enterprise Linux 9: all versions — fixed in 0:344-2.el9_7, 0:356.1-1.el9_8
Red Hat Enterprise Linux 9.6 Extended Update Support: all versions — fixed in 0:334.2-2.el9_6

How to fix

Upgrade to a fixed version: Red Hat Enterprise Linux 10 0:344-3.el10_1, 0:356.1-1.el10_2; Red Hat Enterprise Linux 10.0 Extended Update Support 0:334.1-3.el10_0; Red Hat Enterprise Linux 9 0:344-2.el9_7, 0:356.1-1.el9_8; Red Hat Enterprise Linux 9.6 Extended Update Support 0:334.2-2.el9_6. Check the vendor advisory for mitigations.

References

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