Off-by-one in LibreSSL - #VU153350
Published: October 6, 2026
Vulnerability identifier: #VU153350
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-193
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause incorrect enforcement of certificate-chain depth limits.
The vulnerability exists due to an off-by-one error in the X.509 verifier depth checking when validating certificate chains. A remote attacker can supply a certificate chain to cause incorrect enforcement of certificate-chain depth limits.
Affected software
LibreSSL
Remediation
Install security update from vendor's website.
LibreSSL - addressed in versions 4.2.2, 4.3.3