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.
Affected products
mozilla: firefox
References2
- www.mozilla.org/security/advisories/mfsa2026-53/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2036573 Permissions Required
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 5 · as of 15 November 2026
- CWE
- CWE-79
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