SB2026072298 - Spoofing attack in Firefox for iOS

Description

This security bulletin contains information about 1 vulnerability.

1) Spoofing attack (CVE-ID: CVE-2026-13356)

CWE-ID: CWE-451 - User Interface (UI) Misrepresentation of Critical Information (Clickjacking, spoofing)

CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to spoof the address bar origin.

The vulnerability exists due to improper user interface handling in the browser UI when processing interrupted navigation. A remote attacker can enqueue a synchronous javascript dialog from a malicious webpage to spoof the address bar origin.

The issue occurs when a pending navigation is interrupted, causing the browser to display the destination origin while continuing to render attacker-controlled content.

Remediation

Install update from vendor's website.

References

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-65/
• https://bugzilla.mozilla.org/show_bug.cgi?id=2047768