# Mozilla Firefox (en-US) 99.0

Mozilla Firefox (en-US) 99.0, released April 5, 2022, fixes 10 CVEs in Mozilla Firefox (en-US). None of them is reported as exploited. Patch Radar priority: High. The latest Mozilla Firefox (en-US) is 159.0, which also fixes every one of these CVEs.

- Web page: https://patchblox.com/security/fix/windows-app/mozilla.firefox-99.0
- Platform: Windows apps
- Released: Apr 5, 2022
- Priority: High (Closes CVE-2022-28281, high severity)
- CVEs: 10, exploited: 0, on CISA KEV: 0
- Superseded by: [Mozilla Firefox (en-US) 159.0](https://patchblox.com/security/data/product/windows-app/mozilla-firefox-en-us.md), the latest version, which also fixes every CVE listed here

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Mozilla Firefox (en-US)](https://patchblox.com/security/data/product/windows-app/mozilla-firefox-en-us.md) |  | 99.0 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2022-28281](https://patchblox.com/security/data/cve/CVE-2022-28281.md) | High | Mozilla Thunderbird and 4 others: Out-of-bounds Write | 8.8 | 0.0278 |  |
| [CVE-2022-28282](https://patchblox.com/security/data/cve/CVE-2022-28282.md) | High | Mozilla Thunderbird and 4 others: Use After Free | 8.8 | 0.0218 |  |
| [CVE-2022-1097](https://patchblox.com/security/data/cve/CVE-2022-1097.md) | High | Mozilla Thunderbird and 4 others: Use After Free | 8.8 | 0.0095 |  |
| [CVE-2022-28285](https://patchblox.com/security/data/cve/CVE-2022-28285.md) | High | Mozilla Thunderbird and 4 others: Out-of-bounds Read | 8.8 | 0.0079 |  |
| [CVE-2022-28289](https://patchblox.com/security/data/cve/CVE-2022-28289.md) | High | Mozilla Thunderbird and 4 others: Out-of-bounds Write | 8.8 | 0.0074 |  |
| [CVE-2022-28284](https://patchblox.com/security/data/cve/CVE-2022-28284.md) | High | Mozilla Firefox ESR and 2 others: Improper Encoding or Escaping of Output | 8.8 | 0.0059 |  |
| [CVE-2022-28286](https://patchblox.com/security/data/cve/CVE-2022-28286.md) | High | Mozilla Thunderbird and 4 others: Improper Restriction of Rendered UI Layers or Frames | 8.8 | 0.0058 |  |
| [CVE-2022-28288](https://patchblox.com/security/data/cve/CVE-2022-28288.md) | High | Mozilla Firefox ESR and 2 others: Out-of-bounds Write | 8.8 | 0.0056 |  |
| [CVE-2022-28283](https://patchblox.com/security/data/cve/CVE-2022-28283.md) | Routine | Mozilla Firefox ESR and 2 others: Files or Directories Accessible to External Parties | 6.5 | 0.0060 |  |
| [CVE-2022-28287](https://patchblox.com/security/data/cve/CVE-2022-28287.md) | Routine | Mozilla Firefox ESR and 2 others: Improper Control of a Resource Through its Lifetime | 6.5 | 0.0057 |  |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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