CVE-2026-53900: Vulnerability in Mozilla Firefox for iOS
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.
AI Analysis
Technical Summary
Firefox for iOS improperly preserved cookies set on the initial PDF request across cross-origin HTTP redirects within TemporaryDocument. This flaw enabled a malicious site to inject arbitrary cookies into requests sent to unrelated target domains, potentially compromising cookie integrity and user session security. The vulnerability was addressed and fixed in Firefox for iOS 152.0.
Potential Impact
The vulnerability allows a malicious site to inject arbitrary cookies into requests to unrelated target domains, which could lead to unauthorized cookie manipulation and potential session or authentication issues. The impact is rated high by the vendor.
Mitigation Recommendations
This vulnerability has been fixed in Firefox for iOS version 152.0. Users and administrators should update to Firefox for iOS 152.0 or later to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-53900: Vulnerability in Mozilla Firefox for iOS
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.
CVSS v3.1
Score 4.3medium
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Firefox for iOS improperly preserved cookies set on the initial PDF request across cross-origin HTTP redirects within TemporaryDocument. This flaw enabled a malicious site to inject arbitrary cookies into requests sent to unrelated target domains, potentially compromising cookie integrity and user session security. The vulnerability was addressed and fixed in Firefox for iOS 152.0.
Potential Impact
The vulnerability allows a malicious site to inject arbitrary cookies into requests to unrelated target domains, which could lead to unauthorized cookie manipulation and potential session or authentication issues. The impact is rated high by the vendor.
Mitigation Recommendations
This vulnerability has been fixed in Firefox for iOS version 152.0. Users and administrators should update to Firefox for iOS 152.0 or later to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-11T06:20:46.258Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-56/","vendor":"Mozilla"}]
Threat ID: 6a314c870b89be6888b4cf5a
Added to database: 6/16/2026, 1:15:51 PM
Last enriched: 6/16/2026, 1:30:54 PM
Last updated: 6/17/2026, 4:19:33 AM
Views: 11
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