Description
Firefox for iOS Reader View replaced page content in its HTML template before replacing other internal placeholders. A malicious page could include a placeholder string that was later substituted with JSON-LD data, potentially resulting in arbitrary JavaScript execution. 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=2039422 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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