CVE-2020-6806: High severity Mozilla Firefox vulnerability

Published Mar 10, 2020
·
Updated

By carefully crafting promise resolutions, it was possible to cause an out-of-bounds read off the end of an array resized during script execution. This could have led to memory corruption and a potentially exploitable crash.

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·09:14 PM
Data Sourced
via MITRE·09:14 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:51 PM
Description
Feb 23, 2026
Data Sourced
via Ubuntu·03:19 PM
RemedyDescriptionSeverityAffected Software
Feb 28, 2026
Data Sourced
via Debian·03:23 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2020-6806?

CVE-2020-6806 is a vulnerability in Mozilla Firefox and Thunderbird that allows for an out-of-bounds read off the end of an array during script execution, potentially leading to memory corruption and a crash.

2

How does CVE-2020-6806 affect Mozilla Firefox and Thunderbird?

CVE-2020-6806 affects Mozilla Firefox versions up to 74, Mozilla Thunderbird versions up to 68.6, and Mozilla Firefox ESR versions up to 68.6.

3

What is the severity of CVE-2020-6806?

CVE-2020-6806 has a severity rating of high (7) based on the Common Vulnerability Scoring System (CVSS).

4

How can I fix CVE-2020-6806?

To fix CVE-2020-6806, upgrade Mozilla Firefox to version 74 or later, Mozilla Thunderbird to version 68.6 or later, or Mozilla Firefox ESR to version 68.6 or later.

5

Where can I find more information about CVE-2020-6806?

You can find more information about CVE-2020-6806 on the Mozilla Bugzilla and Mozilla security advisories pages.

Contact

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