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GHSA-337W-H8W7-M899

Vulnerability from github – Published: 2026-01-26 21:30 – Updated: 2026-05-12 15:31
VLAI
Details

A flaw was found in the GnuTLS library, specifically in the gnutls_pkcs11_token_init() function that handles PKCS#11 token initialization. When a token label longer than expected is processed, the function writes past the end of a fixed-size stack buffer. This programming error can cause the application using GnuTLS to crash or, in certain conditions, be exploited for code execution. As a result, systems or applications relying on GnuTLS may be vulnerable to a denial of service or local privilege escalation attacks.

Severity
4.0 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
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{
  "affected": [],
  "aliases": [
    "CVE-2025-9820"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-121"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-26T20:16:09Z",
    "severity": "MODERATE"
  },
  "details": "A flaw was found in the GnuTLS library, specifically in the gnutls_pkcs11_token_init() function that handles PKCS#11 token initialization. When a token label longer than expected is processed, the function writes past the end of a fixed-size stack buffer. This programming error can cause the application using GnuTLS to crash or, in certain conditions, be exploited for code execution. As a result, systems or applications relying on GnuTLS may be vulnerable to a denial of service or local privilege escalation attacks.",
  "id": "GHSA-337w-h8w7-m899",
  "modified": "2026-05-12T15:31:13Z",
  "published": "2026-01-26T21:30:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-9820"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:13812"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:3477"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:4188"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:4655"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:4943"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:5585"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:5606"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:7329"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:7477"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2025-9820"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2392528"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gnutls/gnutls/-/commit/1d56f96f6ab5034d677136b9d50b5a75dff0faf5"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gnutls/gnutls/-/issues/1732"
    },
    {
      "type": "WEB",
      "url": "https://www.gnutls.org/security-new.html#GNUTLS-SA-2025-11-18"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2025/11/20/2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • 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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