CVE catalog
CVE-2021-43540
UBUNTU-CVE-2021-43540
- Severity
- Medium · CVSS 6.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.89% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Ubuntu | firefox | 18.04 | 56.0+build6-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 18.04 | 57.0.1+build2-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 18.04 | 59.0.1+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 18.04 | 59.0.2+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 18.04 | 60.0+build2-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 18.04 | 60.0.1+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 60.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 61.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 61.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 62.0+build2-0ubuntu0.18.04.3 | vulnerable |
| Ubuntu | firefox | 18.04 | 62.0+build2-0ubuntu0.18.04.4 | vulnerable |
| Ubuntu | firefox | 18.04 | 62.0+build2-0ubuntu0.18.04.5 | vulnerable |
| Ubuntu | firefox | 18.04 | 62.0.3+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 63.0+build2-0ubuntu0.18.04.2 | vulnerable |
| Ubuntu | firefox | 18.04 | 63.0.3+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 64.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 65.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 65.0.1+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 66.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 66.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 66.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 66.0.3+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 66.0.4+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 66.0.5+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 67.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 67.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 67.0.2+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 67.0.3+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 67.0.4+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 68.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 68.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 68.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 69.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 69.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 69.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 70.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 70.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 71.0+build5-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 72.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 72.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 73.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 73.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 74.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 74.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 75.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 76.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 76.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 77.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 78.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 78.0.2+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 79.0+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 80.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 80.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 81.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 81.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 82.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 82.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 82.0.3+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 83.0+build2-0ubuntu0.18.04.2 | vulnerable |
| Ubuntu | firefox | 18.04 | 84.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 84.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 84.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 85.0+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 85.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 86.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 86.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 87.0+build3-0ubuntu0.18.04.2 | vulnerable |
| Ubuntu | firefox | 18.04 | 88.0+build2-0ubuntu0.18.04.2 | vulnerable |
| Ubuntu | firefox | 18.04 | 88.0.1+build1-0ubuntu0.18.04.2 | vulnerable |
| Ubuntu | firefox | 18.04 | 89.0+build2-0ubuntu0.18.04.2 | vulnerable |
| Ubuntu | firefox | 18.04 | 89.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 89.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 90.0+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 90.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 91.0+build2-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 91.0.1+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 91.0.2+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 92.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 93.0+build1-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 94.0+build3-0ubuntu0.18.04.1 | vulnerable |
| Ubuntu | firefox | 18.04 | 95.0+build1-0ubuntu0.18.04.1 | fixed |
| Ubuntu | firefox | 20.04 | 69.0.3+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 70.0+build2-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 70.0+build2-0ubuntu2 | vulnerable |
| Ubuntu | firefox | 20.04 | 70.0.1+build1-0ubuntu2 | vulnerable |
| Ubuntu | firefox | 20.04 | 71.0+build2-0ubuntu2 | vulnerable |
| Ubuntu | firefox | 20.04 | 71.0+build5-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 72.0.1+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 72.0.2+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 73.0+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 73.0+build2-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 73.0+build3-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 73.0.1+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 74.0+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 74.0+build2-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 74.0+build2-0ubuntu2 | vulnerable |
| Ubuntu | firefox | 20.04 | 74.0+build3-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 75.0+build3-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 20.04 | 76.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 76.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 77.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 78.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 78.0.2+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 79.0+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 80.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 80.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 81.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 81.0.2+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 82.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 82.0.2+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 82.0.3+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 83.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 84.0+build3-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 84.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 84.0.2+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 85.0+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 85.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 86.0+build3-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 86.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 87.0+build3-0ubuntu0.20.04.2 | vulnerable |
| Ubuntu | firefox | 20.04 | 88.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 88.0.1+build1-0ubuntu0.20.04.2 | vulnerable |
| Ubuntu | firefox | 20.04 | 89.0+build2-0ubuntu0.20.04.2 | vulnerable |
| Ubuntu | firefox | 20.04 | 89.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 89.0.2+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 90.0+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 90.0.2+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 91.0+build2-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 91.0.1+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 91.0.2+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 92.0+build3-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 93.0+build1-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 94.0+build3-0ubuntu0.20.04.1 | vulnerable |
| Ubuntu | firefox | 20.04 | 95.0+build1-0ubuntu0.20.04.1 | fixed |
| Ubuntu | firefox | 22.04 | 93.0+build1-0ubuntu3 | vulnerable |
| Ubuntu | firefox | 22.04 | 94.0+build3-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 22.04 | 94.0.2+build1-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 22.04 | 94.0.2+build2-0ubuntu1 | vulnerable |
| Ubuntu | firefox | 22.04 | 95.0+build1-0ubuntu1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Ubuntu | firefox | deb | 18.04 | 95.0+build1-0ubuntu0.18.04.1 | Not reported | UBUNTU-CVE-2021-43540 | Not reported |
| Ubuntu | firefox | deb | 20.04 | 95.0+build1-0ubuntu0.20.04.1 | Not reported | UBUNTU-CVE-2021-43540 | Not reported |
| Ubuntu | firefox | deb | 22.04 | 95.0+build1-0ubuntu1 | Not reported | UBUNTU-CVE-2021-43540 | Not reported |
OpenFactory catalog packages
No matching packages in this catalog.
Observed: