Improper access control in OpenSSH - CVE-2026-35414
Published: April 29, 2026
Vulnerability identifier: #VU128474
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-35414
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: OpenSSH
Affected software:
OpenSSH
OpenSSH
Detailed vulnerability description
The vulnerability allows a remote user to bypass principal restrictions in certificate-based authentication.
The vulnerability exists due to improper access control in sshd(8) when matching an authorized_keys principals="" option against a list of principals in a certificate. A remote user can present a specially crafted certificate to bypass principal restrictions in certificate-based authentication.
This condition only affects user-trusted CA keys in authorized_keys and requires multiple principals to be listed, including a certificate principal containing a comma character.
How to mitigate CVE-2026-35414
Install security update from vendor's website.