CVE-2026-42013: Improper Certificate Validation in Red Hat Red Hat Enterprise Linux 10
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.
CVE-2026-42013: Improper Certificate Validation in Red Hat Red Hat Enterprise Linux 10
Description
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.
CVSS v3.1
Score 8.2high
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- redhat
- Date Reserved
- 2026-04-23T11:23:46.517Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-42013","vendor":"Red Hat"}]
Threat ID: 6a161534e29bf47b506c5220
Added to database: 05/26/2026, 21:48:36 UTC
Last enriched: 07/21/2026, 18:23:11 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 87
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