CVE-2021-43540: Medium severity firefox vulnerability

Published Dec 7, 2021
·
Updated

WebExtensions with the correct permissions were able to create and install ServiceWorkers for third-party websites that would not have been uninstalled with the extension.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<95
95
Mozilla Firefox<95.0

Event History

Dec 7, 2021
CVE Published
12:00 AM
Dec 8, 2021
CVE Published
via MITRE·09:20 PM
Data Sourced
via MITRE·09:20 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-43540?

CVE-2021-43540 is classified as a moderate severity vulnerability that allows WebExtensions to improperly manage ServiceWorkers.

2

How do I fix CVE-2021-43540?

To mitigate CVE-2021-43540, users should update their Mozilla Firefox browser to version 96 or higher.

3

What are the potential impacts of CVE-2021-43540?

CVE-2021-43540 could allow third-party websites to retain ServiceWorkers even after the uninstallation of the associated WebExtension.

4

Which versions of Firefox are affected by CVE-2021-43540?

CVE-2021-43540 affects Mozilla Firefox versions prior to 96.

5

Who is responsible for addressing CVE-2021-43540?

Mozilla is responsible for addressing and patching CVE-2021-43540 in its Firefox browser.

Contact

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