CRITICAL
CVE-2026-100804
CVSS v3
9.6
CRITICAL
EPSS Score
—
exploit probability
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Sandbox escape due to use-after-free in the Preferences: Backend component. This vulnerability was fixed in Firefox 157.
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- Published
- 2026-09-29
- Last Modified
- 2026-09-29
Frequently asked questions
What is CVE-2026-100804?
Sandbox escape due to use-after-free in the Preferences: Backend component. This vulnerability was fixed in Firefox 157.
Is CVE-2026-100804 actively exploited?
Active exploitation of CVE-2026-100804 has not been confirmed.
What is the CVSS score for CVE-2026-100804?
CVE-2026-100804 has a CVSS v3 base score of 9.6 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.
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