Origin validation error in Mozilla products - CVE-2026-124874
Published: November 10, 2026
Vulnerability identifier: #VU164502
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-2026-124874
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 information across web origins.
The vulnerability exists due to improper enforcement of the same-origin policy in the Networking: HTTP component when handling HTTP operations. A remote attacker can supply crafted web content that triggers incorrectly authorized cross-origin operations to potentially access information belonging to another origin.
Affected software
Firefox for Android
Mozilla Firefox
Firefox ESR
Mozilla Firefox
Firefox ESR
How to mitigate CVE-2026-124874
Install security update from vendor's website.
Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0
Firefox ESR - addressed in versions 115.45.0, 153.7.0
Mozilla Firefox - update to 160.0
Firefox ESR - addressed in versions 115.45.0, 153.7.0