CVE-2026-0884

CRITICAL 9.8CVE-2026-0884 · Published 13/01/2026 · updated 17/06/2026

Package	Affected versions	Patched versions
firefox mozilla	`< 140.7.0< 147.0`	`140.7.0147.0`
thunderbird mozilla	`< 140.7.0< 147.0`	`140.7.0147.0`

Description

Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.

References

bugzilla.mozilla.org/show_bug.cgi · Permissions Required
mozilla.org/security/advisories/mfsa2026-01 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-03 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-04 · Vendor Advisory
mozilla.org/security/advisories/mfsa2026-05 · Vendor Advisory

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