{
  "cveId": "CVE-2021-29977",
  "url": "https://patchblox.com/security/cve/CVE-2021-29977",
  "summary": "CVE-2021-29977 is fixed in 4 products on 2 platforms, first by firefox 90.0\u002Bbuild1-0ubuntu0.18.04.1, released July 14, 2021. It is not reported as exploited. Patch Radar priority: High.",
  "title": "Firefox ESR and 1 other: Mozilla developers reported memory safety bugs present in Firefox 89.",
  "description": "Mozilla developers reported memory safety bugs present in Firefox 89. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox \u003C 90.",
  "published": "2021-07-14T17:00:00Z",
  "severity": "Medium",
  "cvss": 8.8,
  "epss": 0.01009,
  "epssPercentile": 0.63301,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://nvd.nist.gov/vuln/detail/CVE-2021-29977",
  "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": "90.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "firefox 90.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-90.0-build1-0ubuntu0.18.04.1",
      "released": "2021-07-14T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "90.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "firefox 90.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-90.0-build1-0ubuntu0.20.04.1",
      "released": "2021-07-14T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-geckodriver",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "90.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "firefox-geckodriver 90.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-geckodriver-90.0-build1-0ubuntu0.18.04.1",
      "released": "2021-07-14T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-geckodriver",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "90.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "firefox-geckodriver 90.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-geckodriver-90.0-build1-0ubuntu0.20.04.1",
      "released": "2021-07-14T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-mozsymbols",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "90.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "firefox-mozsymbols 90.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-mozsymbols-90.0-build1-0ubuntu0.18.04.1",
      "released": "2021-07-14T17:00:00Z"
    },
    {
      "platform": "linux",
      "product": "firefox-mozsymbols",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "90.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "firefox-mozsymbols 90.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-firefox-mozsymbols-90.0-build1-0ubuntu0.20.04.1",
      "released": "2021-07-14T17:00:00Z"
    }
  ],
  "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"
  }
}