CVE-2026-117997

CVSS 9.6 (critical) · published 2026-10-27

Sandbox escape due to use-after-free in the Widget component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.

Weakness: CWE-416

Source: NVD CVE-2026-117997

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2081560
• https://www.mozilla.org/security/advisories/mfsa2026-118/
• https://www.mozilla.org/security/advisories/mfsa2026-120/
• https://www.mozilla.org/security/advisories/mfsa2026-121/
• https://www.mozilla.org/security/advisories/mfsa2026-122/

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