CVE-2026-84119

EUVD-2026-69064
Sandbox escape due to use-after-free in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
9.6 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
vulnerable
firefox-esr
bookworm
vulnerable
bookworm (security)
vulnerable
forky
vulnerable
sid
vulnerable
trixie
vulnerable
trixie (security)
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
firefox
jammy
not-affected
noble
not-affected
resolute
not-affected
thunderbird
jammy
needed
noble
not-affected
resolute
not-affected
mozjs38
bionic
needs-triage
jammy
dne
noble
dne
resolute
dne
mozjs52
bionic
ignored
focal
ignored
jammy
dne
noble
dne
resolute
dne
mozjs68
focal
ignored
jammy
dne
noble
dne
resolute
dne
mozjs78
jammy
ignored
noble
dne
resolute
dne
mozjs91
jammy
ignored
noble
dne
resolute
dne
mozjs102
jammy
ignored
noble
ignored
resolute
dne
mozjs115
jammy
dne
noble
ignored
resolute
dne
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2057817
https://www.mozilla.org/security/advisories/mfsa2026-82/
https://www.mozilla.org/security/advisories/mfsa2026-83/
https://www.mozilla.org/security/advisories/mfsa2026-84/
https://www.mozilla.org/security/advisories/mfsa2026-85/
https://www.mozilla.org/security/advisories/mfsa2026-86/
https://www.mozilla.org/security/advisories/mfsa2026-87/
https://www.mozilla.org/security/advisories/mfsa2026-88/