CVE-2021-43540
Last modified
CVE-2021-43540 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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 estimates a 0.86% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 95.0 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1636629Issue Tracking, Permissions Required, Vendor Advisory
- https://security.gentoo.org/glsa/202202-03Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-52/Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1636629Issue Tracking, Permissions Required, Vendor Advisory
- https://security.gentoo.org/glsa/202202-03Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-52/Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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