CVE-2026-8960
High
Description
Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Mozilla Firefox
PublishedMay 19, 2026
First seenMay 19, 2026
Weakness typeCWE-290CWE-290
How to fix
Update
- mozilla firefox151.0.0 or later
- mozilla thunderbird151.0.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 151.0.0 | 151.0.0 |
| mozilla thunderbird | v < 151.0.0 | 151.0.0 |
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