CVE-2026-16366
High
Description
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Mozilla Firefox
PublishedJul 21, 2026
First seenJul 21, 2026
Weakness typeCWE-269Improper privilege management
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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