Main Vulnerability Database Vulnerabilities #VU156063

Protection mechanism failure in Mozilla Firefox and Firefox for Android - CVE-2026-109755

Published: October 16, 2026

Vulnerability identifier: #VU156063

CSH Severity: Medium

CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-109755

CWE-ID: CWE-693

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to escape sandbox restrictions.

The vulnerability exists due to inadequate sandbox-boundary enforcement in the DOM: Content Processes component when handling content-process operations. A remote attacker can exploit the flawed isolation controls to perform operations outside the intended sandbox restrictions.

Affected software

Mozilla Firefox
Firefox for Android

How to mitigate CVE-2026-109755

Install security update from vendor's website.

Mozilla Firefox - update to 158.0
Firefox for Android - update to 158.0

External References

Related Security Bulletins