Search: CVE-2026-74939

CVE-2026-74939 is a high-severity privilege escalation vulnerability in the DOM Navigation component of Mozilla Firefox. It allows an unprivileged user interface action to escalate privileges within the browser. This vulnerability was fixed in Firefox 154 and Firefox ESR versions 115.39, 140.14, and 153.1, as well as corresponding Thunderbird versions. The vulnerability has a CVSS score of 8.8, indicating high impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported. Mozilla has officially patched this issue.