CVE-2025-1020
Critical
Description
Memory safety bugs present in Firefox 134 and Thunderbird 134. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 135 and Thunderbird 135.
SeverityCritical
CVSS9.8
Exploit probability—
Product
Mozilla Firefox
PublishedFeb 4, 2025
First seenFeb 4, 2025
Weakness typeCWE-787Out-of-bounds write
How to fix
Update
- mozilla firefox135.0 or later
- mozilla thunderbird135.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 135.0 | 135.0 |
| mozilla thunderbird | 131.0 ≤ v < 135.0 | 135.0 |
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