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GHSA-2PW7-G86G-76Q7

Vulnerability from github – Published: 2026-05-27 00:31 – Updated: 2026-09-03 15:31
VLAI
Details

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
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{
  "affected": [],
  "aliases": [
    "CVE-2026-42013"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1284",
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-26T22:16:42Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-2pw7-g86g-76q7",
  "modified": "2026-09-03T15:31:53Z",
  "published": "2026-05-27T00:31:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42013"
    },
    {
      "type": "WEB",
      "url": "https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-8"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467448"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-42013"
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  "schema_version": "1.4.0",
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      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}



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