CVE-2025-9185
High
Description
Memory safety bugs present in Firefox ESR 115.26, Firefox ESR 128.13, Thunderbird ESR 128.13, Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141. 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 142, Firefox ESR 115.27, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.
SeverityHigh
CVSS8.1
Exploit probability—
Product
Mozilla Firefox
PublishedAug 19, 2025
First seenAug 19, 2025
Weakness typeCWE-119Memory buffer bounds error
How to fix
Update
- mozilla firefox115.27.0, 142.0, 128.14.0, 140.2.0 or later
- mozilla thunderbird128.14.0, 142.0, 140.2.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 115.27.0, v < 142.0, 128.0 ≤ v < 128.14.0, 140.0 ≤ v < 140.2.0 | 115.27.0, 142.0, 128.14.0, 140.2.0 |
| mozilla thunderbird | v < 128.14.0, v < 142.0, 140.0 ≤ v < 140.2.0 | 128.14.0, 142.0, 140.2.0 |
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