CVE-2026-103418

Universal XSS via the HTML language attribute in Translation Services

Published Oct 13, 2026 CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed
Description
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Weaknesses CWE-79
Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox For Ios
Vendors & Products Mozilla
Mozilla firefox For Ios
Type Values Removed Values Added
Description Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.
Title Universal XSS via the HTML language attribute in Translation Services
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mozilla
Published
Updated
Oct 14, 2026, 3:58 AM
Reserved
Sep 30, 2026, 2:48 PM
Status
Deferred
Published
Oct 13, 2026, 8:16 AM
Modified
Oct 14, 2026, 4:18 AM