{
  "cveId": "CVE-2021-23974",
  "url": "https://patchblox.com/security/cve/CVE-2021-23974",
  "summary": "CVE-2021-23974 is fixed in 4 products on 2 platforms, first by firefox 86.0\u002Bbuild3-0ubuntu0.18.04.1, released February 26, 2021. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "Firefox ESR and 1 other: The DOMParser API did not properly process \u0027\u003Cnoscript\u003E\u0027 elements for escaping.",
  "description": "The DOMParser API did not properly process \u0027\u003Cnoscript\u003E\u0027 elements for escaping. This could be used as an mXSS vector to bypass an HTML Sanitizer. This vulnerability affects Firefox \u003C 86.",
  "published": "2021-02-25T18:15:00Z",
  "severity": "Medium",
  "cvss": 6.1,
  "epss": 0.00753,
  "epssPercentile": 0.55291,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://nvd.nist.gov/vuln/detail/CVE-2021-23974",
  "fixes": [
    {
      "platform": "windows-app",
      "product": "Mozilla Firefox ESR (en-US)",
      "fixedVersion": "91.0",
      "fix": "Mozilla Firefox ESR (en-US) 91.0",
      "url": "https://patchblox.com/security/fix/windows-app/mozilla.firefox.esr-91.0",
      "released": "2021-08-04T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "86.0\u002Bbuild3-0ubuntu0.18.04.1",
      "fix": "firefox 86.0\u002Bbuild3-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-86.0-build3-0ubuntu0.18.04.1",
      "released": "2021-02-26T08:15:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "86.0\u002Bbuild3-0ubuntu0.20.04.1",
      "fix": "firefox 86.0\u002Bbuild3-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-86.0-build3-0ubuntu0.20.04.1",
      "released": "2021-02-26T08:15:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-geckodriver",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "86.0\u002Bbuild3-0ubuntu0.18.04.1",
      "fix": "firefox-geckodriver 86.0\u002Bbuild3-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-geckodriver-86.0-build3-0ubuntu0.18.04.1",
      "released": "2021-02-26T08:15:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-geckodriver",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "86.0\u002Bbuild3-0ubuntu0.20.04.1",
      "fix": "firefox-geckodriver 86.0\u002Bbuild3-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-geckodriver-86.0-build3-0ubuntu0.20.04.1",
      "released": "2021-02-26T08:15:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-mozsymbols",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "86.0\u002Bbuild3-0ubuntu0.18.04.1",
      "fix": "firefox-mozsymbols 86.0\u002Bbuild3-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-mozsymbols-86.0-build3-0ubuntu0.18.04.1",
      "released": "2021-02-26T08:15:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-mozsymbols",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "86.0\u002Bbuild3-0ubuntu0.20.04.1",
      "fix": "firefox-mozsymbols 86.0\u002Bbuild3-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-mozsymbols-86.0-build3-0ubuntu0.20.04.1",
      "released": "2021-02-26T08:15:00Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T00:53:09Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}