CVE-2020-6811: Command Injection

Published Mar 10, 2020
·
Updated

Last updated 25 August 2025

Other sources

The 'Copy as cURL' feature of Devtools' network tab did not properly escape the HTTP method of a request, which can be controlled by the website. If a user used the 'Copy as Curl' feature and pasted the command into a terminal, it could have resulted in command injection and arbitrary command execution.

— Mozilla

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 to a version that resolves this vulnerability.

    Fixed in 68.6
  10. Operational

    If users used Devtools 'Copy as cURL'/'Copy as Curl' and pasted the generated command into a terminal, treat it as potentially malicious: review terminal history and rotate any exposed credentials used during that session.

Event History

Mar 10, 2020
CVE Published
via Mozilla·12:00 AM
Mar 25, 2020
CVE Published
via MITRE·09:12 PM
Data Sourced
via MITRE·09:12 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:52 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-2020-6811?

CVE-2020-6811 is a vulnerability in Mozilla Firefox and Thunderbird that allows command injection and arbitrary command execution.

2

How does CVE-2020-6811 work?

CVE-2020-6811 works by not properly escaping the HTTP method of a request in the 'Copy as cURL' feature of Devtools' network tab.

3

Which software is affected by CVE-2020-6811?

Mozilla Firefox (up to version 74), Thunderbird (up to version 68.6), and Firefox ESR (up to version 68.6) are affected by CVE-2020-6811.

4

What is the severity of CVE-2020-6811?

The severity of CVE-2020-6811 is rated as medium.

5

How can I fix CVE-2020-6811?

To fix CVE-2020-6811, update Mozilla Firefox to version 75 or later, Thunderbird to version 68.7 or later, or Firefox ESR to version 68.7 or later.

Company

Resources

Contact

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