CVE-2020-6813: Medium severity Mozilla Firefox vulnerability

Published Mar 10, 2020
·
Updated

Last updated 25 August 2025

Other sources

When protecting CSS blocks with the nonce feature of Content Security Policy, the @import statement in the CSS block could allow an attacker to inject arbitrary styles, bypassing the intent of the Content Security Policy.

Affected Software

3 affected componentsFixes available
Mozilla Firefox<74
74
Mozilla Firefox<74.0
debian/firefox
147.0.4-1

Event History

Mar 10, 2020
CVE Published
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
Data Sourced
via Debian·03:20 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is vulnerability CVE-2020-6813?

Vulnerability CVE-2020-6813 is a security flaw in Mozilla Firefox that allows an attacker to inject arbitrary styles by bypassing the Content Security Policy.

2

How does vulnerability CVE-2020-6813 affect Mozilla Firefox?

Vulnerability CVE-2020-6813 affects Mozilla Firefox versions up to version 74. It allows an attacker to inject arbitrary styles by bypassing the Content Security Policy.

3

What is the severity of vulnerability CVE-2020-6813?

The severity of vulnerability CVE-2020-6813 is low.

4

How can I fix vulnerability CVE-2020-6813 in Mozilla Firefox?

To fix vulnerability CVE-2020-6813 in Mozilla Firefox, update to version 74 or higher.

5

Where can I find more information about vulnerability CVE-2020-6813?

You can find more information about vulnerability CVE-2020-6813 on Mozilla's website and Bugzilla.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203