CVE-2026-9309
Received Received - Intake
Firefox for iOS Reader View HTML Injection Leads to XSS

Publication date: 2026-06-01

Last updated on: 2026-06-01

Assigner: Mozilla Corporation

Description
Firefox for iOS Reader View did not properly escape HTML tags in JSON-LD metadata. A malicious page could inject markup that changed Reader View behavior and leaked sensitive URL parameters. These parameters could then be used to access internal pages, potentially resulting in arbitrary JavaScript execution in an internal origin. This vulnerability was fixed in Firefox for iOS 151.2.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-06-01
Last Modified
2026-06-01
Generated
2026-06-01
AI Q&A
2026-06-01
EPSS Evaluated
N/A
NVD
EUVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
mozilla firefox_for_ios 151.2
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Powered Q&A
What immediate steps should I take to mitigate this vulnerability?

To mitigate this vulnerability, update Firefox for iOS to version 151.2 or later, where the issue with improper HTML tag escaping in JSON-LD metadata within Reader View has been fixed.


Can you explain this vulnerability to me?

This vulnerability in Firefox for iOS Reader View occurs because HTML tags in JSON-LD metadata were not properly escaped.

A malicious webpage could exploit this flaw by injecting markup that changes how Reader View behaves and causes sensitive URL parameters to be leaked.

These leaked parameters could then be used to access internal pages and potentially allow arbitrary JavaScript execution within an internal origin.


How can this vulnerability impact me? :

The impact of this vulnerability includes the exposure of sensitive URL parameters which could lead to unauthorized access to internal pages.

Additionally, it could enable an attacker to execute arbitrary JavaScript code within an internal origin, potentially compromising the security and integrity of the application.


How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:

The provided information does not specify how this vulnerability affects compliance with common standards and regulations such as GDPR or HIPAA.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart