CVE-2026-8706: Vulnerability in Mozilla Firefox for iOS
Firefox for iOS hosted Reader mode on an unauthenticated local web server, allowing another application on the same device to request arbitrary URLs and receive the response rendered with the signed-in user's cookies. This vulnerability was fixed in Firefox for iOS 151.0.
AI Analysis
Technical Summary
Firefox for iOS implemented Reader mode by hosting an unauthenticated local web server. This design flaw permitted other applications on the same iOS device to send requests to arbitrary URLs through this local server and receive the responses rendered with the cookies of the signed-in Firefox user. This behavior could expose sensitive user data to unauthorized applications. Mozilla addressed and fixed this vulnerability in Firefox for iOS 151.0, as documented in their security advisory MFSA 2026-49.
Potential Impact
The vulnerability allows other applications on the same iOS device to access web content rendered with the signed-in user's cookies via the Reader mode local server. This can lead to leakage of sensitive user data, including session cookies, potentially enabling unauthorized access to user accounts or private information. The impact is rated high by Mozilla.
Mitigation Recommendations
This vulnerability is fixed in Firefox for iOS version 151.0. Users and administrators should update to this version or later to remediate the issue. No additional mitigation steps are required as the fix is official and complete.
CVE-2026-8706: Vulnerability in Mozilla Firefox for iOS
Description
Firefox for iOS hosted Reader mode on an unauthenticated local web server, allowing another application on the same device to request arbitrary URLs and receive the response rendered with the signed-in user's cookies. This vulnerability was fixed in Firefox for iOS 151.0.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Firefox for iOS implemented Reader mode by hosting an unauthenticated local web server. This design flaw permitted other applications on the same iOS device to send requests to arbitrary URLs through this local server and receive the responses rendered with the cookies of the signed-in Firefox user. This behavior could expose sensitive user data to unauthorized applications. Mozilla addressed and fixed this vulnerability in Firefox for iOS 151.0, as documented in their security advisory MFSA 2026-49.
Potential Impact
The vulnerability allows other applications on the same iOS device to access web content rendered with the signed-in user's cookies via the Reader mode local server. This can lead to leakage of sensitive user data, including session cookies, potentially enabling unauthorized access to user accounts or private information. The impact is rated high by Mozilla.
Mitigation Recommendations
This vulnerability is fixed in Firefox for iOS version 151.0. Users and administrators should update to this version or later to remediate the issue. No additional mitigation steps are required as the fix is official and complete.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-15T19:32:40.967Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-49/","vendor":"Mozilla"}]
Threat ID: 6a0c870dec166c07b0be159c
Added to database: 5/19/2026, 3:51:41 PM
Last enriched: 5/19/2026, 4:06:44 PM
Last updated: 5/19/2026, 5:20:43 PM
Views: 6
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