VULNERABILITY INTELLIGENCE
CVE-2020-26959
CVSS score8.8 HIGH
EPSS probability1.30%
CISA KEVNot currently listed
Published2020-12-09
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Description
During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Weakness classification
- nvd@nist.gov: CWE-416
Primary references
- security@mozilla.org — Issue Tracking, Permissions Required, Vendor Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Permissions Required, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Vendor Advisory