8.8
High
CVE-2026-109739 Privilege escalation in the WebExtensions component
Description
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 158 | earliest → < 158 | 158 |
| Thunderbird 158 | earliest → < 158 | 158 |
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