vulnerability
Debian: CVE-2021-23978: firefox-esr, thunderbird -- security update
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Feb 26, 2021 | Feb 26, 2021 | Mar 30, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Feb 26, 2021
Added
Feb 26, 2021
Modified
Mar 30, 2026
Description
Mozilla developers reported memory safety bugs present in Firefox 85 and Firefox ESR 78.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.
Solutions
debian-upgrade-firefox-esrdebian-upgrade-thunderbird
Rapid7 Labs
2026 Global Threat Landscape Report
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