CVE-2026-84126
Medium
Description
Incorrect boundary conditions in the Layout: Grid component. This vulnerability was fixed in Firefox 155 and Thunderbird 155.
SeverityMedium
CVSS4.3
Exploit probability—
Product
Mozilla Firefox
PublishedSep 1, 2026
First seenSep 1, 2026
Weakness typeCWE-120CWE-120
How to fix
Update
- mozilla firefox155.0.0 or later
- mozilla thunderbird155.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 155.0.0 | 155.0.0 |
| mozilla thunderbird | v < 155.0 | 155.0 |
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