CVE-2026-109750
Critical
Description
Site isolation issue in the DOM: Web Authentication component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
SeverityCritical
CVSS9.6
Exploit probability—
ProductFirefox
PublishedOct 13, 2026
First seenOct 13, 2026
Weakness typeCWE-862Missing authorization
How to fix
Update
- Firefox158 or later
- Thunderbird158 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox | No range specified | 158 |
| Thunderbird | No range specified | 158 |
Check your version
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