{
  "cveId": "CVE-2021-29964",
  "url": "https://patchblox.com/security/cve/CVE-2021-29964",
  "summary": "CVE-2021-29964 is fixed in 2 products on 1 platform, first by Mozilla Thunderbird (en-US) 78.11.0, released May 28, 2021. It is not reported as exploited. Patch Radar priority: High.",
  "title": "Firefox ESR and 3 others: A locally-installed hostile program could send \u0060WM_COPYDATA\u0060 messages that Firefox would process incorrectly,\u2026",
  "description": "A locally-installed hostile program could send \u0060WM_COPYDATA\u0060 messages that Firefox would process incorrectly, leading to an out-of-bounds read. *This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird \u003C 78.11, Firefox \u003C 89, and Firefox ESR \u003C 78.11.",
  "published": "2021-06-24T14:15:10Z",
  "severity": "",
  "cvss": 7.1,
  "epss": 0.00816,
  "epssPercentile": 0.57357,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://nvd.nist.gov/vuln/detail/CVE-2021-29964",
  "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": "windows-app",
      "product": "Mozilla Thunderbird (en-US)",
      "fixedVersion": "78.11.0",
      "fix": "Mozilla Thunderbird (en-US) 78.11.0",
      "url": "https://patchblox.com/security/fix/windows-app/mozilla.thunderbird-78.11.0",
      "released": "2021-05-28T00:00:00Z"
    }
  ],
  "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"
  }
}