Vulnerability in Mozilla Firefox
CVE-2021-43540
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.
EPSS: 0.009 (54.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.
Affected products
- Mozilla Firefox — versions unspecified
References
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (Permissions Required, x_refsource_MISC, Issue Tracking, Vendor Advisory)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2021-43540?
- CVE-2021-43540 is a medium-severity vulnerability in Mozilla Firefox. CVSS score: 6.5/10. Published 2021-12-08.
- How severe is CVE-2021-43540?
- Medium severity. CVSS v3 base score is 6.5 out of 10.