CVE-2021-43540

Published: Dec 8, 2021Modified: Jun 17, 2026

6.5

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Exploitability: 2.8 / Impact: 3.6

Source: NVD

Description

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. This vulnerability affects Firefox < 95.

Affected (1)

Products: Mozilla: Firefox

Mozilla

1 product

Firefox

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Mozilla Firefox	Before 95.0

References (6)

https://bugzilla.mozilla.org/show_bug.cgi?id=1636629

Source: security@mozilla.org

Issue TrackingPermissions RequiredVendor Advisory

https://security.gentoo.org/glsa/202202-03

Source: security@mozilla.org

Third Party Advisory

https://www.mozilla.org/security/advisories/mfsa2021-52/

Source: security@mozilla.org

Vendor Advisory

https://bugzilla.mozilla.org/show_bug.cgi?id=1636629

Source: af854a3a-2127-422b-91ae-364da2661108

Issue TrackingPermissions RequiredVendor Advisory

https://security.gentoo.org/glsa/202202-03

Source: af854a3a-2127-422b-91ae-364da2661108

Third Party Advisory

https://www.mozilla.org/security/advisories/mfsa2021-52/

Source: af854a3a-2127-422b-91ae-364da2661108

Vendor Advisory

Timeline

No history available yet.