Vulnerability 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 Score
HIGH
Related Weaknesses (CWE)
References
- https://access.redhat.com/errata/RHSA-2026:13274
- https://access.redhat.com/errata/RHSA-2026:20611
- https://access.redhat.com/errata/RHSA-2026:20612
- https://access.redhat.com/errata/RHSA-2026:20613
- https://access.redhat.com/errata/RHSA-2026:26319
- https://access.redhat.com/errata/RHSA-2026:26409
- https://access.redhat.com/errata/RHSA-2026:29197
- https://access.redhat.com/errata/RHSA-2026:30004
- https://access.redhat.com/errata/RHSA-2026:30849
- https://access.redhat.com/errata/RHSA-2026:30850
- https://access.redhat.com/errata/RHSA-2026:32962
- https://access.redhat.com/errata/RHSA-2026:33125
- https://access.redhat.com/errata/RHSA-2026:40762
- https://access.redhat.com/errata/RHSA-2026:41921
- https://access.redhat.com/errata/RHSA-2026:43575
FAQ
What is CVE-2026-42013?
CVE-2026-42013 is a vulnerability with a CVSS score of 8.2 (HIGH). 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...
How severe is CVE-2026-42013?
CVE-2026-42013 has been rated HIGH with a CVSS base score of 8.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42013?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.