CVE-2021-23960
8.8
HIGH
CVSS 3.1
EPSS 0.29%
Description
Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
How to fix CVE-2021-23960
To remediate CVE-2021-23960, upgrade the affected package to a fixed version below.
- Debian/firefox-esr—upgrade to 78.7.0esr-1 or later
- Debian/thunderbird—upgrade to 1:78.7.0-1 or later
Is CVE-2021-23960 being exploited?
Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 78.7.0esr-1
- from 0, < 1:78.7.0-1
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 |