— Unscored

Use-after-free in the JavaScript: GC component.

CVE-2026-117865

Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.

Assessment

CVSS: Not yet scored
Severity: Unscored
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 27 October 2026
Last updated: 27 October 2026
Assigner: security@mozilla.org

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