CVE-2025-6430
Medium
Description
When a file download is specified via the `Content-Disposition` header, that directive would be ignored if the file was included via a `<embed>` or `<object>` tag, potentially making a website vulnerable to a cross-site scripting attack. This vulnerability was fixed in Firefox 140, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.
SeverityMedium
CVSS6.1
Exploit probability—
Product
Mozilla Firefox
PublishedJun 24, 2025
First seenJun 24, 2025
Weakness typeCWE-79Cross-site scripting (XSS)
How to fix
Update
- mozilla firefox128.12.0, 140.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 128.12.0, v < 140.0 | 128.12.0, 140.0 |
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