CVE-2025-11712
Medium
Description
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability was fixed in Firefox 144, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.
SeverityMedium
CVSS6.1
Exploit probability—
Product
Mozilla Firefox
PublishedOct 14, 2025
First seenOct 14, 2025
Weakness typeCWE-116CWE-116
How to fix
Update
- mozilla firefox140.4.0, 144.0 or later
- mozilla thunderbird140.4.0, 144.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 140.4.0, v < 144.0 | 140.4.0, 144.0 |
| mozilla thunderbird | v < 140.4.0, 141.0 ≤ v < 144.0 | 140.4.0, 144.0 |
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