CVE-2026-42013CWE-295

CVE-2026-42013

High · published May 27, 2026

CVSS v3.1
8.2
EPSS
1%
Percentile
46.1
In the wild
Unconfirmed
What it is

A flaw was found in gnutls. When validating certificates, an oversized Subject Alternative Name (SAN) could cause the validation process to incorrectly fall back to checking the Common Name (CN) field. This could allow a remote attacker to bypass proper certificate validation, potentially leading to spoofing or man-in-the-middle attacks.

The record
Technical detail
CVSS v3.1
8.2 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00564 · 46.1th percentile
Weakness
CWE-295 · Improper Certificate Validation
Published
2026-05-27T02:16Z
References (32)
https://access.redhat.com/errata/RHSA-2026:13274 · [email protected]https://access.redhat.com/errata/RHSA-2026:20611 · [email protected]https://access.redhat.com/errata/RHSA-2026:20612 · [email protected]https://access.redhat.com/errata/RHSA-2026:20613 · [email protected]https://access.redhat.com/errata/RHSA-2026:26319 · [email protected]https://access.redhat.com/errata/RHSA-2026:26409 · [email protected]https://access.redhat.com/errata/RHSA-2026:29197 · [email protected]https://access.redhat.com/errata/RHSA-2026:30004 · [email protected]https://access.redhat.com/errata/RHSA-2026:30849 · [email protected]https://access.redhat.com/errata/RHSA-2026:30850 · [email protected]https://access.redhat.com/errata/RHSA-2026:32962 · [email protected]https://access.redhat.com/errata/RHSA-2026:33125 · [email protected]https://access.redhat.com/errata/RHSA-2026:40762 · [email protected]https://access.redhat.com/errata/RHSA-2026:41921 · [email protected]https://access.redhat.com/errata/RHSA-2026:43575 · [email protected]https://access.redhat.com/errata/RHSA-2026:56853 · [email protected]https://access.redhat.com/errata/RHSA-2026:57483 · [email protected]https://access.redhat.com/errata/RHSA-2026:58981 · [email protected]https://access.redhat.com/errata/RHSA-2026:59831 · [email protected]https://access.redhat.com/errata/RHSA-2026:60019 · [email protected]https://access.redhat.com/errata/RHSA-2026:72502 · [email protected]https://access.redhat.com/errata/RHSA-2026:74674 · [email protected]https://access.redhat.com/errata/RHSA-2026:82304 · [email protected]https://access.redhat.com/errata/RHSA-2026:82322 · [email protected]https://access.redhat.com/errata/RHSA-2026:82347 · [email protected]https://access.redhat.com/errata/RHSA-2026:82354 · [email protected]https://access.redhat.com/errata/RHSA-2026:82372 · [email protected]https://access.redhat.com/errata/RHSA-2026:82857 · [email protected]https://access.redhat.com/errata/RHSA-2026:82888 · [email protected]https://access.redhat.com/security/cve/CVE-2026-42013 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2467448 · [email protected]https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-8 · [email protected]
EPSS history
Timeline
  • 26 MAY 21:29Z
    Gnutls: gnutls: certificate validation bypass due to oversized subject alternative name
    cvelistv5