{
  "cveId": "CVE-2021-29952",
  "url": "https://patchblox.com/security/cve/CVE-2021-29952",
  "summary": "CVE-2021-29952 is fixed in 4 products on 2 platforms, first by firefox 88.0.1\u002Bbuild1-0ubuntu0.18.04.2, released May 6, 2021. It is not reported as exploited. Patch Radar priority: High.",
  "title": "Firefox ESR and 1 other: When Web Render components were destructed, a race condition could have caused undefined behavior, and\u2026",
  "description": "When Web Render components were destructed, a race condition could have caused undefined behavior, and we presume that with enough effort may have been exploitable to run arbitrary code. This vulnerability affects Firefox \u003C 88.0.1 and Firefox for Android \u003C 88.1.3.",
  "published": "2021-05-06T17:00:00Z",
  "severity": "Medium",
  "cvss": 7.5,
  "epss": 0.00736,
  "epssPercentile": 0.54704,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://nvd.nist.gov/vuln/detail/CVE-2021-29952",
  "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": "88.0.1\u002Bbuild1-0ubuntu0.18.04.2",
      "fix": "firefox 88.0.1\u002Bbuild1-0ubuntu0.18.04.2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-88.0.1-build1-0ubuntu0.18.04.2",
      "released": "2021-05-06T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "88.0.1\u002Bbuild1-0ubuntu0.20.04.2",
      "fix": "firefox 88.0.1\u002Bbuild1-0ubuntu0.20.04.2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-88.0.1-build1-0ubuntu0.20.04.2",
      "released": "2021-05-06T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-geckodriver",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "88.0.1\u002Bbuild1-0ubuntu0.18.04.2",
      "fix": "firefox-geckodriver 88.0.1\u002Bbuild1-0ubuntu0.18.04.2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-geckodriver-88.0.1-build1-0ubuntu0.18.04.2",
      "released": "2021-05-06T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-geckodriver",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "88.0.1\u002Bbuild1-0ubuntu0.20.04.2",
      "fix": "firefox-geckodriver 88.0.1\u002Bbuild1-0ubuntu0.20.04.2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-geckodriver-88.0.1-build1-0ubuntu0.20.04.2",
      "released": "2021-05-06T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-mozsymbols",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "88.0.1\u002Bbuild1-0ubuntu0.18.04.2",
      "fix": "firefox-mozsymbols 88.0.1\u002Bbuild1-0ubuntu0.18.04.2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-mozsymbols-88.0.1-build1-0ubuntu0.18.04.2",
      "released": "2021-05-06T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-mozsymbols",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "88.0.1\u002Bbuild1-0ubuntu0.20.04.2",
      "fix": "firefox-mozsymbols 88.0.1\u002Bbuild1-0ubuntu0.20.04.2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-mozsymbols-88.0.1-build1-0ubuntu0.20.04.2",
      "released": "2021-05-06T17:00:00Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}