Gnutls: gnutls: certificate validation bypass due to oversized subject alternative name
Historical advisory recorded 11 Nov 2026 13:57:25 UTC. Read the latest advisory.
cve-program · CVE-2026-42013
PublishedA 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.
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cve-program · CVE-2026-42013
PublishedGnutls: gnutls: certificate validation bypass due to oversized subject alternative name
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.
- Source published
- 26 May 2026 21:29:32 UTC
- Source modified
- 11 Nov 2026 12:41:33 UTC
- Saved here
- 11 Nov 2026 13:57:25 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 3.1 · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N