CVE-2026-16389
Critical
Description
Incorrect boundary conditions, integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
SeverityCritical
CVSS9.8
Exploit probability—
Product
Mozilla Firefox
PublishedJul 21, 2026
First seenJul 21, 2026
Weakness typeCWE-190Integer overflow
How to fix
Update
- mozilla firefox153.0.0 or later
- mozilla thunderbird153.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 153.0.0 | 153.0.0 |
| mozilla thunderbird | v < 153.0 | 153.0 |
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