# CERT-FR Flags Firefox Security Bypass Flaw

Published: 2026-10-07 · Severity: routine
Canonical: https://vorant.io/reports/8b040cfc-421f-5e22-b2b3-b10cbb3467f6/cert-fr-flags-firefox-security-bypass-flaw

> A CERT-FR advisory warns of a security policy bypass vulnerability in Firefox versions before 157.0.1, patched by Mozilla.

CERT-FR published an advisory describing a vulnerability affecting Mozilla Firefox versions prior to 157.0.1. The flaw allows an attacker to cause a bypass of the browser's security policy, as referenced in Mozilla's security bulletin mfsa2026-104 (October 6, 2026) and tracked as CVE-2026-106016. The advisory does not indicate active exploitation in the wild.

Defenders should update affected Firefox installations to version 157.0.1 or later as provided by Mozilla. No further technical details, exploit status, or indicators of compromise were included in the bulletin; organizations should monitor Mozilla's official advisory for additional context and apply patches through standard update channels.

## Mentioned in this report

- Vulnerabilities: CVE-2026-106016

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1272

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