CVE-2025-14321
Critical
Description
Use-after-free in the WebRTC: Signaling component. This vulnerability was fixed in Firefox 146, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.
SeverityCritical
CVSS9.8
Exploit probability—
Product
Mozilla Firefox
PublishedDec 9, 2025
First seenDec 9, 2025
Weakness typeCWE-416Use after free
How to fix
Update
- mozilla firefox140.6.0, 146.0 or later
- mozilla thunderbird140.6.0, 146.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 140.6.0, v < 146.0 | 140.6.0, 146.0 |
| mozilla thunderbird | v < 140.6.0, v < 146.0 | 140.6.0, 146.0 |
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