CVE-2026-42013 (GCVE-0-2026-42013)

Vulnerability from cvelistv5 – Published: 2026-05-26 21:29 – Updated: 2026-05-26 21:29
VLAI
Title
Gnutls: gnutls: certificate validation bypass due to oversized subject alternative name
Summary
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.
Severity
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
CWE
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Assigner
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-42013 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2467448 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-04-29 00:00
Credits
Red Hat would like to thank Haruto Kimura (Stella) and Joshua Rogers (AISLE Research Team) for reporting this issue.
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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