9.8
Critical
CVE-2025-6424 A use-after-free in FontFaceSet resulted in a potentially exploitable crash
Description
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. 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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