CVE-2026-6731CWE-295

X.509 name constraint bypass via Subject CN treated as a DNS name

Medium · published June 25, 2026

CVSS v4.0
6.0
EPSS
0%
Percentile
1.9
In the wild
Unconfirmed
What it is

X.509 name constraint bypass via the Subject Common Name when treated as a DNS-type name. A certificate whose Subject CN violates an issuing CA's DNS name constraints could be accepted.

The record
Technical detail
CVSS v4.0
6.0 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
EPSS
0.00124 · 1.9th percentile
Weakness
CWE-295 · Improper Certificate Validation
Published
2026-06-25T20:08Z
EPSS history
Timeline
  • 25 JUN 20:08Z
    X.509 name constraint bypass via Subject CN treated as a DNS name
    cvelistv5