# CVE-2022-22753: Mozilla Firefox ESR and 4 others: Time-of-check Time-of-use (TOCTOU) Race Condition

CVE-2022-22753 is fixed in 3 products on 1 platform, first by Mozilla Firefox (en-US) 97.0, released February 8, 2022. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2022-22753
- Priority: High
- CVSS: 7.1
- EPSS: 0.0065
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 22, 2022
- Weakness: CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2022-22753

## Description

A Time-of-Check Time-of-Use bug existed in the Maintenance (Updater) Service that could be abused to grant Users write access to an arbitrary directory. This could have been used to escalate to SYSTEM access.<br>*This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox (en-US) | 97.0 | [Mozilla Firefox (en-US) 97.0](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox-97.0.md) | Feb 8, 2022 |
| Windows apps | Mozilla Firefox ESR (en-US) | 102.0 | [Mozilla Firefox ESR (en-US) 102.0](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-102.0.md) | Jun 23, 2022 |
| Windows apps | Mozilla Thunderbird (en-US) | 91.6.0 | [Mozilla Thunderbird (en-US) 91.6.0](https://patchblox.com/security/data/fix/windows-app/mozilla.thunderbird-91.6.0.md) | Feb 8, 2022 |

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Data as of 2026-11-08T06:59:42Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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