CVE-2026-53900
Medium
Description
Firefox for iOS preserved cookies set on the initial PDF request across cross-origin HTTP redirects in TemporaryDocument, allowing a malicious site to inject arbitrary cookies into requests to an unrelated target domain. This vulnerability was fixed in Firefox for iOS 152.0.
SeverityMedium
CVSS4.3
Exploit probability—
Product
Mozilla Firefox Mobile
PublishedJun 16, 2026
First seenJun 16, 2026
Weakness typeCWE-345CWE-345CWE-384CWE-384
How to fix
Update
- mozilla firefox_mobile152.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox_mobile | v < 152.0 | 152.0 |
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