Firefox for iOS security bypass flaw patched
CERT-FR advises updating Firefox for iOS before version 155.0 to fix a security policy bypass vulnerability.
Sourcecert.ssi.gouv.fr — open the original
What to check
- Applies to
- The 1 CVE named below. Whether you run an affected version is not assessed: check the versions the source lists.
- Exploitation
- No exploitation in the wild and no public exploit is recorded for the CVEs named.
CERT-FR issued an advisory regarding a vulnerability in Mozilla Firefox for iOS affecting all versions prior to 155.0. The flaw, tracked as CVE-2026-81267, allows an attacker to bypass the browser's security policy, as detailed in Mozilla's security bulletin mfsa2026-81 published on 31 August 2026. No exploitation in the wild is indicated in this advisory.
Organizations and users running Firefox for iOS are advised to update to version 155.0 or later as soon as possible to remediate the vulnerability. No further technical detail on exploitation vector or impact scope beyond the security bypass classification was provided in the source bulletin.
Mentioned in this report
Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1099
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