CVE-2026-42012: Improper Certificate Validation
A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted certificate that contains Uniform Resource Identifier (URI) or Service (SRV) Subject Alternative Names (SANs). This could cause the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN), potentially allowing the attacker to spoof legitimate services or intercept sensitive information.
CVE-2026-42012: Improper Certificate Validation
Description
A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted certificate that contains Uniform Resource Identifier (URI) or Service (SRV) Subject Alternative Names (SANs). This could cause the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN), potentially allowing the attacker to spoof legitimate services or intercept sensitive information.
CVSS v3.1
Score 7.1high
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- redhat
- Date Reserved
- 2026-04-23T11:23:46.517Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-42012","vendor":"Red Hat"}]
Threat ID: 6a161534e29bf47b506c521c
Added to database: 05/26/2026, 21:48:36 UTC
Last enriched: 07/21/2026, 18:22:57 UTC
Last updated: 09/10/2026, 19:36:53 UTC
Views: 220
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