CVE-2021-23995
8.8
HIGH
CVSS 3.1
EPSS 0.77%
Description
When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
How to fix CVE-2021-23995
To remediate CVE-2021-23995, upgrade the affected package to a fixed version below.
- Debian/firefox-esr—upgrade to 78.10.0esr-1 or later
- —upgrade to 1:78.10.0-1 or later
Is CVE-2021-23995 being exploited?
Low — EPSS is 0.8%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 78.10.0esr-1
- from 0, < 1:78.10.0-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |