cbcvebase.
CVE-2021-43540
published 2021-12-08

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…

PriorityP427medium6.5CVSS 3.1
AVNACLPRNUIRSUCNIHAN
EPSS
0.86%
54.1th percentile
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

9 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 95.0-1 (sid)firefox 95.0-1 (sid)
mozillafirefox< 95.095.0
mozillafirefox
mozillafirefox>= 0 < 95.0.1+build2-0ubuntu0.18.04.195.0.1+build2-0ubuntu0.18.04.1
mozillafirefox>= 0 < 95.0+build1-0ubuntu0.18.04.195.0+build1-0ubuntu0.18.04.1
mozillafirefox>= 0 < 95.0.1+build2-0ubuntu0.20.04.195.0.1+build2-0ubuntu0.20.04.1
mozillafirefox>= 0 < 95.0+build1-0ubuntu0.20.04.195.0+build1-0ubuntu0.20.04.1
mozillafirefox>= 0 < 95.0+build1-0ubuntu195.0+build1-0ubuntu1
mozillafirefox>= unspecified < 9595

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:P/A:N
osv6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_ubuntu6.5MEDIUM
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