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CVE

DEBIAN-CVE-2026-84121

Sandbox escape due to use-after-free in the DOM: Security component.
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CVE

DEBIAN-CVE-2026-84121

Sandbox escape due to use-after-free in the DOM: Security component.

Sandbox escape due to use-after-free in the DOM: Security 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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
-
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
C
H
U
-

Related Resources

No items found.

References

https://security-tracker.debian.org/tracker/CVE-2026-84121

Severity

9.6

CVSS Score
0
10

Basic Information

Base CVSS
9.6
EPSS Probability
0%
EPSS Percentile
0%
Introduced Version
0
Fix Available
140.15.0esr-1~deb12u1,140.15.0esr-1~deb13u1,140.15.0esr-1,1:140.15.0esr-1~deb12u1,1:140.15.0esr-1~deb13u1,1:153.2.0esr-1

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