# CERT-FR flags Firefox iOS vulnerabilities

Published: 2026-10-13 · Severity: routine
Canonical: https://vorant.io/reports/b0a20343-0c1a-56a1-8295-972ca8590322/cert-fr-flags-firefox-ios-vulnerabilities

> CERT-FR advisory warns of two vulnerabilities in Firefox for iOS before 157.1 enabling XSS and security policy bypass; patch available.

CERT-FR published an advisory describing multiple vulnerabilities in Mozilla Firefox for iOS, affecting versions prior to 157.1. The flaws, tracked as CVE-2026-103417 and CVE-2026-103418, allow an attacker to perform indirect remote code injection (cross-site scripting) and bypass security policy controls. The advisory references Mozilla's own security bulletin (MFSA2026-105) published 05 October 2026.

No evidence of active exploitation is mentioned in the advisory. Defenders and users should update affected Firefox for iOS installations to version 157.1 or later as provided by Mozilla's official channels. This is a routine vendor patch advisory relayed by CERT-FR with no indication of in-the-wild attacks or targeted campaigns.

## Mentioned in this report

- Vulnerabilities: CVE-2026-103417, CVE-2026-103418

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1297

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