4.3
Medium
CVE-2025-6425 An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that…
Description
An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted between containers and normal/private browsing mode, but not profiles. This vulnerability was fixed in Firefox 140, Firefox ESR 115.25, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 140 | earliest → < 140 | 140 |
| Firefox 128.12 | earliest → < 128.12 | 128.12 |
| Firefox 115.25 | earliest → < 115.25 | 115.25 |
| Firefox ESR 128.12 | earliest → < 128.12 | 128.12 |
| Thunderbird 140 | earliest → < 140 | 140 |
| Thunderbird 128.12 | earliest → < 128.12 | 128.12 |
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