Main Vulnerability Database Vulnerabilities #VU156069

Input validation error in Mozilla Firefox and Firefox for Android - CVE-2026-109773

Published: October 16, 2026

Vulnerability identifier: #VU156069

CSH Severity: Low

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

CVE-ID: CVE-2026-109773

CWE-ID: CWE-20

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a processing flaw in the Sync component when handling synchronization operations. A remote attacker can trigger the affected processing behavior to disrupt availability.

Affected software

Mozilla Firefox
Firefox for Android

How to mitigate CVE-2026-109773

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