Improper isolation or compartmentalization in Mozilla products - CVE-2026-124913
Published: November 10, 2026
Vulnerability identifier: #VU164545
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-124913
CWE-ID: CWE-653
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to weaken site isolation, potentially accessing resources across site boundaries.
The vulnerability exists due to insufficient site isolation enforcement in the Networking component when handling network activity. A remote attacker can trigger affected networking behavior to cross intended site boundaries and potentially access otherwise isolated resources.
Affected software
Firefox ESR
Mozilla Firefox
Firefox for Android
Mozilla Firefox
Firefox for Android
How to mitigate CVE-2026-124913
Install security update from vendor's website.
Firefox ESR - update to 153.7.0
Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0
Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0