CVE-2026-42013
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.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.2
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
- EPSS probability
- 0.42%
- CWE
- CWE-1284, CWE-295
- Published
- 2026-05-26
- Last modified
- 2026-09-14
Affected products
- Red Hat Red Hat Enterprise Linux 8
- Red Hat Red Hat Enterprise Linux 10
- Red Hat Red Hat Enterprise Linux 9
- Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support
- Red Hat Red Hat Update Infrastructure 5
- Red Hat Red Hat Update Infrastructure 5
- Red Hat Red Hat Update Infrastructure 5
- Red Hat Red Hat Update Infrastructure 5
Weakness type
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