CVE-2025-8040
High
Description
Memory safety bugs present in Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. 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 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Mozilla Firefox
PublishedJul 22, 2025
First seenJul 22, 2025
Weakness typeCWE-119Memory buffer bounds error
How to fix
Update
- mozilla firefox140.1, 141.0 or later
- mozilla thunderbird140.1, 141.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 140.1, v < 141.0 | 140.1, 141.0 |
| mozilla thunderbird | v < 140.1, v < 141.0 | 140.1, 141.0 |
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