7.5
High
CVE-2026-16399 Site isolation issue in the DOM: Navigation component
Description
Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 153 | earliest → < 153 | 153 |
| Thunderbird 153 | earliest → < 153 | 153 |