CVE-2025-5269
High
Description
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 128.11 and Thunderbird 128.11.
SeverityHigh
CVSS8.1
Exploit probability—
Product
Mozilla Firefox
PublishedMay 27, 2025
First seenMay 27, 2025
Weakness typeCWE-787Out-of-bounds write
How to fix
Update
- mozilla firefox128.11.0 or later
- mozilla thunderbird128.11.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 128.11.0 | 128.11.0 |
| mozilla thunderbird | v < 128.11.0 | 128.11.0 |
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