CVE-2013-4314

HIGH7.5EPSS 0.25%

pyopenssl - hostname check bypassing

Published: 5/17/2022Modified: 4/28/2026

Description

The X509Extension in pyOpenSSL before 0.13.1 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority.

Affected packages (4)

CVSS scores

SourceVersionSeverityVector
osvCVSS 4.0CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
osvCVSS 3.1HIGH7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References (11)