{
  "cveId": "CVE-2021-43528",
  "url": "https://patchblox.com/security/cve/CVE-2021-43528",
  "summary": "CVE-2021-43528 is fixed in 7 products on 2 platforms, first by Mozilla Thunderbird (en-US) 91.4.0, released December 3, 2021. It is not reported as exploited. Patch Radar priority: High.",
  "title": "Mozilla Thunderbird and 1 other: Thunderbird unexpectedly enabled JavaScript in the composition area.",
  "description": "Thunderbird unexpectedly enabled JavaScript in the composition area. The JavaScript execution context was limited to this area and did not receive chrome-level privileges, but could be used as a stepping stone to further an attack with other vulnerabilities. This vulnerability affects Thunderbird \u003C 91.4.0.",
  "published": "2021-12-08T14:15:00Z",
  "severity": "Important",
  "cvss": 9.8,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.01309,
  "epssPercentile": 0.70781,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://nvd.nist.gov/vuln/detail/CVE-2021-43528",
  "fixes": [
    {
      "platform": "windows-app",
      "product": "Mozilla Thunderbird (en-US)",
      "fixedVersion": "91.4.0",
      "fix": "Mozilla Thunderbird (en-US) 91.4.0",
      "url": "https://patchblox.com/security/fix/windows-app/mozilla.thunderbird-91.4.0",
      "released": "2021-12-03T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "1:91.4.0-1",
      "fix": "DEBIAN-CVE-2021-43528",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-43528",
      "released": "2021-12-08T22:15:09Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "1:91.4.0-1",
      "fix": "DEBIAN-CVE-2021-43528",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-43528",
      "released": "2021-12-08T22:15:09Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "Debian 14",
      "fixedVersion": "1:91.4.0-1",
      "fix": "DEBIAN-CVE-2021-43528",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-43528",
      "released": "2021-12-08T22:15:09Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "RHEL 8",
      "fixedVersion": "0:91.4.0-2.el8_5",
      "fix": "RHSA-2021:5045",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2021-5045",
      "released": "2021-12-09T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "thunderbird 1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-thunderbird-1-91.5.0-build1-0ubuntu0.18.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "thunderbird 1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-thunderbird-1-91.5.0-build1-0ubuntu0.20.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "almalinux 8",
      "fixedVersion": "91.4.0-2.el8_5.alma",
      "fix": "ALSA-2021:5045",
      "url": "https://patchblox.com/security/fix/linux/alsa-2021-5045",
      "released": "2021-12-09T12:14:59Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "ol 8",
      "fixedVersion": "0:91.4.0-2.0.1.el8_5",
      "fix": "ELSA-2021-5045",
      "url": "https://patchblox.com/security/fix/linux/elsa-2021-5045",
      "released": "2021-12-10T00:00:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird",
      "release": "rocky 8",
      "fixedVersion": "0:91.4.0-2.el8_5",
      "fix": "RLSA-2021:5045",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2021-5045",
      "released": "2021-12-09T12:14:59Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird-gnome-support",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "thunderbird-gnome-support 1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-91.5.0-build1-0ubuntu0.18.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird-gnome-support",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "thunderbird-gnome-support 1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-thunderbird-gnome-support-1-91.5.0-build1-0ubuntu0.20.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird-mozsymbols",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "thunderbird-mozsymbols 1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-91.5.0-build1-0ubuntu0.18.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "thunderbird-mozsymbols",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "thunderbird-mozsymbols 1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-thunderbird-mozsymbols-1-91.5.0-build1-0ubuntu0.20.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "xul-ext-calendar-timezones",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "xul-ext-calendar-timezones 1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-91.5.0-build1-0ubuntu0.18.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "xul-ext-calendar-timezones",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "xul-ext-calendar-timezones 1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-xul-ext-calendar-timezones-1-91.5.0-build1-0ubuntu0.20.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "xul-ext-gdata-provider",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "xul-ext-gdata-provider 1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-91.5.0-build1-0ubuntu0.18.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "xul-ext-gdata-provider",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "xul-ext-gdata-provider 1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-xul-ext-gdata-provider-1-91.5.0-build1-0ubuntu0.20.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "xul-ext-lightning",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "fix": "xul-ext-lightning 1:91.5.0\u002Bbuild1-0ubuntu0.18.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-xul-ext-lightning-1-91.5.0-build1-0ubuntu0.18.04.1",
      "released": "2023-02-16T14:15:00Z"
    },
    {
      "platform": "linux",
      "product": "xul-ext-lightning",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "fix": "xul-ext-lightning 1:91.5.0\u002Bbuild1-0ubuntu0.20.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-xul-ext-lightning-1-91.5.0-build1-0ubuntu0.20.04.1",
      "released": "2023-02-16T14:15:00Z"
    }
  ],
  "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"
  }
}