CVE-2026-84123
High
Description
Privilege escalation due to use-after-free in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Mozilla Firefox
PublishedSep 1, 2026
First seenSep 1, 2026
Weakness typeCWE-416Use after free
How to fix
Update
- mozilla firefox153.2.0, 155.0.0 or later
- mozilla thunderbird153.2.0, 155.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 153.2.0, 154.0.0 ≤ v < 155.0.0 | 153.2.0, 155.0.0 |
| mozilla thunderbird | v < 153.2.0, 154.0 ≤ v < 155.0 | 153.2.0, 155.0 |
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