cbcvebase.
CVE-2021-23984
published 2021-03-31

CVE-2021-23984: A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable…

PriorityP429medium6.5CVSS 3.1
AVNACLPRNUIRSUCNIHAN
EPSS
1.11%
62.0th percentile
A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.

Affected

19 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 87.0-1 (sid)firefox 87.0-1 (sid)
debianfirefox-esr< firefox 87.0-1 (sid)firefox 87.0-1 (sid)
debianthunderbird< firefox 87.0-1 (sid)firefox 87.0-1 (sid)
mozillafirefox< 87.087.0
mozillafirefox
mozillafirefox>= 0 < 87.0+build3-0ubuntu0.16.04.287.0+build3-0ubuntu0.16.04.2
mozillafirefox>= 0 < 87.0+build3-0ubuntu0.18.04.287.0+build3-0ubuntu0.18.04.2
mozillafirefox>= 0 < 87.0+build3-0ubuntu0.20.04.287.0+build3-0ubuntu0.20.04.2
mozillafirefox>= unspecified < 8787
mozillafirefox_esr< 78.978.9
mozillafirefox_esr>= unspecified < 78.978.9
mozillathunderbird< 78.978.9
mozillathunderbird>= 0 < 1:78.9.0-11:78.9.0-1
mozillathunderbird>= 0 < 1:78.9.0-11:78.9.0-1
mozillathunderbird>= 0 < 1:78.9.0-11:78.9.0-1
mozillathunderbird>= 0 < 1:78.9.0-11:78.9.0-1
mozillathunderbird>= 0 < 1:78.11.0+build1-0ubuntu0.18.04.21:78.11.0+build1-0ubuntu0.18.04.2
mozillathunderbird>= 0 < 1:78.11.0+build1-0ubuntu0.20.04.21:78.11.0+build1-0ubuntu0.20.04.2
mozillathunderbird>= unspecified < 78.978.9

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
osv8.1HIGH
vendor_ubuntu8.1HIGH
vendor_debian6.5MEDIUM
vendor_redhat6.5MEDIUM
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