CVE-2026-2797

CriticalCVSS 9.8

Published: 24/02/2026(UTC)Updated: 15/07/2026(UTC)Translated: 16/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.32%

24th percentile - higher than 24% of all known CVEs

Summary

A use-after-free vulnerability was found in the JavaScript: GC component of Firefox and Thunderbird. This flaw was fixed in versions 148 of both products.

Risk Assessment

An attacker could exploit this vulnerability to execute arbitrary code remotely or cause a denial of service, compromising system confidentiality and availability.

Recommendation

Immediately update Firefox and Thunderbird to version 148 or later.

Other vulnerabilities in Firefox

See all

CVE-2026-106016Critical
A vulnerability in the file handling component of the Firefox browser allows bypassing security mitigations. The issue was fixed in version 157.0.1.
CVE-2026-100829Critical
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
CVE-2026-100828Critical
Mitigation bypass in the Bookmarks & History component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
CVE-2026-100819Critical
Sandbox escape due to incorrect boundary conditions in the XPCOM component. Fixed in multiple Firefox and Thunderbird versions.
CVE-2026-100818Critical
Sandbox escape due to use-after-free in the Widget: Gtk component. Fixed in multiple Firefox and Thunderbird versions.
CVE-2026-100811Critical
Sandbox escape due to use-after-free in the DOM: Core & HTML component. Fixed in multiple Firefox and Thunderbird versions.
CVE-2026-100810Critical
Other issue in the DevTools component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.
CVE-2026-100804Critical
Sandbox escape due to use-after-free in the Preferences: Backend component. Fixed in Thunderbird 157 and Firefox 157.
CVE-2026-100800Critical
Sandbox escape due to use-after-free in the Disability Access APIs component. Fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
CVE-2026-100794Critical
Vulnerability allows sandbox escape due to incorrect boundary conditions in the Internationalization component. It was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.

Original NVD description (English source)

Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS