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
152.0.6-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.13.0esr-1~deb11u1140.12.0esr-1~deb12u1140.13.0esr-1~deb12u1140.12.0esr-1~deb13u1140.13.0esr-1~deb13u1140.12.0esr-1140.13.0esr-2
debian/thunderbird
1:115.12.0-1~deb11u11:140.12.0esr-1~deb11u11:140.12.0esr-1~deb12u11:140.12.0esr-1~deb13u11:140.12.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/firefox to a version that resolves this vulnerability.

    Fixed in 68.6
  2. Upgrade

    Upgrade redhat/thunderbird to a version that resolves this vulnerability.

    Fixed in 68.6
  3. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 68.6
  4. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 74
  5. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 68.6
  6. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 152.0.6-1
  7. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 115.14.0esr-1~deb11u1Fixed in 140.13.0esr-1~deb11u1Fixed in 140.12.0esr-1~deb12u1Fixed in 140.13.0esr-1~deb12u1Fixed in 140.12.0esr-1~deb13u1Fixed in 140.13.0esr-1~deb13u1Fixed in 140.12.0esr-1Fixed in 140.13.0esr-2
  8. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:115.12.0-1~deb11u1Fixed in 1:140.12.0esr-1~deb11u1Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:140.12.0esr-1
  9. Upgrade

    Upgrade mozilla Thunderbird / Firefox / Firefox ESR to a version that resolves this vulnerability.

    Fixed in 68.6
  10. Upgrade

    Upgrade mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 74
  11. Compensating control

    Update Thunderbird/Firefox/Firefox ESR installations to versions that are not affected by CVE-2020-6806 to prevent out-of-bounds reads that could lead to memory corruption and exploitable crashes.

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
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:51 PM
Description
Feb 23, 2026
Data Sourced
via Ubuntu·03:19 PM
RemedyDescriptionSeverityAffected Software
Jul 24, 2026
Data Sourced
via Debian·04:21 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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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.

Company

Resources

Contact

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