CVE-2020-6814: Critical severity Mozilla Firefox vulnerability

Published Mar 10, 2020
·
Updated

Last updated 25 August 2025

Other sources

Mozilla developers and community members Byron Campen, Jason Kratzer, and Christian Holler reported memory safety bugs present in Firefox 73 and Firefox ESR 68.5. 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.

Mozilla

Mozilla developers and community members reported memory safety bugs present in Firefox 73 and Firefox ESR 68.5. 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.

External Reference:

https://www.mozilla.org/en-US/security/advisories/mfsa2020-09/#CVE-2020-6814

Red Hat

Mozilla developers Byron Campen, Jason Kratzer, and Christian Holler reported memory safety bugs present in Firefox 73 and Firefox ESR 68.5. 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.

Mozilla developers Byron Campen, Jason Kratzer, and Christian Holler reported memory safety bugs present in Thunderbird 68.5. 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.

Mozilla

Mozilla developers reported memory safety bugs present in Firefox and Thunderbird 68.5. 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 Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

Launchpad

Affected Software

14 affected componentsFixes available
redhat/firefox<68.6
68.6
redhat/thunderbird<68.6
68.6
Mozilla Firefox<74.0
Mozilla Firefox ESR<68.6.0
Mozilla Thunderbird<68.6.0
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=19.10
Mozilla Thunderbird<68.6
68.6
Mozilla Firefox<74
74
Mozilla Firefox ESR<68.6
68.6
debian/firefox
148.0-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.7.0esr-1~deb11u1128.14.0esr-1~deb12u1140.8.0esr-1~deb12u1140.4.0esr-1~deb13u1140.8.0esr-1~deb13u1140.7.0esr-1140.8.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.8.0esr-1~deb11u11:140.6.0esr-1~deb12u11:140.8.0esr-1~deb12u11:140.6.0esr-1~deb13u11:140.8.0esr-1~deb13u11:140.7.1esr-11:140.8.0esr-1

Event History

Mar 10, 2020
CVE Published
via Mozilla·12:00 AM
Mar 25, 2020
CVE Published
via MITRE·09:11 PM
Data Sourced
via MITRE·09:11 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:52 PM
Description
Feb 23, 2026
Data Sourced
via Ubuntu·03:19 PM
RemedyDescriptionSeverityAffected Software
Feb 28, 2026
Data Sourced
via Debian·03:24 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2020-6814?

CVE-2020-6814 is a vulnerability reported in Mozilla Firefox 73 and Firefox ESR 68.5 that involves memory safety bugs with evidence of memory corruption.

2

How severe is CVE-2020-6814?

CVE-2020-6814 has a severity rating of high (7) based on the Common Vulnerability Scoring System (CVSS).

3

Which software versions are affected by CVE-2020-6814?

Mozilla Firefox versions up to exclusive 74, Mozilla Thunderbird versions up to exclusive 68.6, and Mozilla Firefox ESR versions up to exclusive 68.6 are affected by CVE-2020-6814.

4

How can CVE-2020-6814 be exploited?

CVE-2020-6814 could have been exploited with enough effort due to the memory corruption caused by the memory safety bugs.

5

Where can I find more information about CVE-2020-6814?

You can find more information about CVE-2020-6814 on the Mozilla Bugzilla and Mozilla Security Advisories websites.

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