High 2 exploited CVEs DSA-4653-1 2 CVEs

firefox-esr - security update

Published Apr 4, 2020 · Updated Mar 9, 2026

Ecosystem: Debian

Fixed packages 2

Release	Package	Fixed in
Debian · 10	firefox-esr	68.6.1esr-1~deb10u1
Debian · 9	firefox-esr	68.6.1esr-1~deb9u1

Vulnerabilities 2

High 8.1

CVE-2020-6819 Exploited

Under certain conditions, when running the nsDocShell destructor, a race condition can cause a use-after-free. We are a…

Mozilla Firefox Thunderbird Firefox ESR Browsers Debian Ubuntu Alpine

Apr 24, 2020
KEV Nov 3, 2021
High 8.1

CVE-2020-6820 Exploited

Under certain conditions, when handling a ReadableStream, a race condition can cause a use-after-free. We are aware of …

Mozilla Firefox Thunderbird Firefox ESR Browsers Debian Ubuntu Alpine

Apr 24, 2020
KEV Nov 3, 2021