CVE-2025-6424
Critical
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.
SeverityCritical
CVSS9.8
Exploit probability—
Product
Mozilla Firefox
PublishedJun 24, 2025
First seenJun 24, 2025
Weakness typeCWE-416Use after free
How to fix
Update
- mozilla firefox115.25.0, 140.0, 128.12.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 115.25.0, v < 140.0, 116.0 ≤ v < 128.12.0 | 115.25.0, 140.0, 128.12.0 |
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