{
  "cveId": "CVE-2021-20231",
  "url": "https://patchblox.com/security/cve/CVE-2021-20231",
  "summary": "CVE-2021-20231 is fixed in 13 products on 1 platform, first by gnutls-bin 3.6.13-2ubuntu1.6, released March 12, 2021. It is not reported as exploited. Patch Radar priority: High.",
  "title": "gnutls: The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorit...",
  "description": "The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorithms and protocols such as SSL, TLS, and DTLS.\n\nNettle is a cryptographic library that is designed to fit easily in almost any context: In crypto toolkits for object-oriented languages, such as C\u002B\u002B, Python, or Pike, in applications like LSH or GNUPG, or even in kernel space.\n\nThe following packages have been upgraded to a later upstream version: gnutls (3.6.16). (BZ#1956783)\n\nSecurity Fix(es):\n\n* nettle: Remote crash in RSA decryption via manipulated ciphertext (CVE-2021-3580)\n\n* gnutls: Use after free in client key_share extension (CVE-2021-20231)\n\n* gnutls: Use after free in client_send_params in lib/ext/pre_shared_key.c (CVE-2021-20232)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n\nAdditional Changes:\n\nFor detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.",
  "published": "2021-03-12T11:15:00Z",
  "severity": "Moderate",
  "cvss": 9.8,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.03678,
  "epssPercentile": 0.89748,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "gnutls",
      "release": "RHEL 8",
      "fixedVersion": "0:3.6.16-4.el8",
      "fix": "RHSA-2021:4451",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2021-4451",
      "released": "2021-11-09T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "gnutls",
      "release": "almalinux 8",
      "fixedVersion": "3.6.16-4.el8",
      "fix": "ALSA-2021:4451",
      "url": "https://patchblox.com/security/fix/linux/alsa-2021-4451",
      "released": "2021-11-09T09:23:20Z"
    },
    {
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      "product": "gnutls",
      "release": "ol 8",
      "fixedVersion": "0:3.6.16-4.el8",
      "fix": "ELSA-2021-4451",
      "url": "https://patchblox.com/security/fix/linux/elsa-2021-4451",
      "released": "2021-11-16T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "gnutls",
      "release": "rocky 8",
      "fixedVersion": "0:3.6.16-4.el8",
      "fix": "RLSA-2021:4451",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2021-4451",
      "released": "2021-11-09T09:23:20Z"
    },
    {
      "platform": "linux",
      "product": "gnutls-bin",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "3.6.13-2ubuntu1.6",
      "fix": "gnutls-bin 3.6.13-2ubuntu1.6",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-gnutls-bin-3.6.13-2ubuntu1.6",
      "released": "2021-03-12T11:15:00Z"
    },
    {
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      "product": "gnutls-c\u002B\u002B",
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      "fixedVersion": "0:3.6.16-4.el8",
      "fix": "RHSA-2021:4451",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2021-4451",
      "released": "2021-11-09T00:00:00Z"
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    {
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      "product": "gnutls-c\u002B\u002B",
      "release": "almalinux 8",
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      "fix": "ALSA-2021:4451",
      "url": "https://patchblox.com/security/fix/linux/alsa-2021-4451",
      "released": "2021-11-09T09:23:20Z"
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    {
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      "fix": "ELSA-2021-4451",
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      "released": "2021-11-16T00:00:00Z"
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    {
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      "fix": "RHSA-2021:4451",
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      "released": "2021-11-09T00:00:00Z"
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      "fix": "ALSA-2021:4451",
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      "fix": "ELSA-2021-4451",
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      "released": "2021-03-12T11:15:00Z"
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      "released": "2021-03-12T11:15:00Z"
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  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
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}