vulnerability
Debian: CVE-2020-26959: firefox-esr, thunderbird -- security update
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Nov 20, 2020 | Nov 20, 2020 | Mar 30, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Nov 20, 2020
Added
Nov 20, 2020
Modified
Mar 30, 2026
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.
Solutions
debian-upgrade-firefox-esrdebian-upgrade-thunderbird
Rapid7 Labs
2026 Global Threat Landscape Report
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