Origin validation error in Mozilla products - CVE-2026-117860

 

Origin validation error in Mozilla products - CVE-2026-117860

Published: October 27, 2026


Vulnerability identifier: #VU158141
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-117860
CWE-ID: CWE-346
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to bypass the same-origin policy and potentially access cross-origin information.

The vulnerability exists due to improper origin validation in the DOM: Navigation component when handling navigation. A remote attacker can supply crafted web content to cross origin boundaries and potentially access otherwise restricted information.


Affected software

Firefox ESR
Mozilla Firefox
Firefox for Android

How to mitigate CVE-2026-117860

Install security update from vendor's website.

Firefox ESR - update to 153.6.0
Firefox for Android - update to 159.0
Mozilla Firefox - update to 159.0

External References

Related Security Bulletins