8.8
High
CVE-2026-109778 Privilege escalation in the WebExtensions component
Description
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 158 | earliest → < 158 | 158 |
| Firefox 153.5 | earliest → < 153.5 | 153.5 |
| Thunderbird 158 | earliest → < 158 | 158 |
| Thunderbird 153.5 | earliest → < 153.5 | 153.5 |
References
- bugzilla.mozilla.org bugzilla.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
Timeline
- Published
- Last modified
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