cbcvebase.
CVE-2021-23999
published 2021-06-24

CVE-2021-23999: If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should…

PriorityP342high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
1.28%
66.4th percentile
If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

Affected

19 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 88.0-1 (sid)firefox 88.0-1 (sid)
debianfirefox-esr< firefox 88.0-1 (sid)firefox 88.0-1 (sid)
debianthunderbird< firefox 88.0-1 (sid)firefox 88.0-1 (sid)
mozillafirefox< 88.088.0
mozillafirefox
mozillafirefox>= 0 < 88.0+build2-0ubuntu0.16.04.188.0+build2-0ubuntu0.16.04.1
mozillafirefox>= 0 < 88.0+build2-0ubuntu0.18.04.288.0+build2-0ubuntu0.18.04.2
mozillafirefox>= 0 < 88.0+build2-0ubuntu0.20.04.188.0+build2-0ubuntu0.20.04.1
mozillafirefox>= unspecified < 8888
mozillafirefox_esr< 78.1078.10
mozillafirefox_esr>= unspecified < 78.1078.10
mozillathunderbird< 78.1078.10
mozillathunderbird>= 0 < 1:78.10.0-11:78.10.0-1
mozillathunderbird>= 0 < 1:78.10.0-11:78.10.0-1
mozillathunderbird>= 0 < 1:78.10.0-11:78.10.0-1
mozillathunderbird>= 0 < 1:78.10.0-11:78.10.0-1
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 < 78.1078.10

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
osv8.8HIGH
vendor_debian8.8HIGH
vendor_redhat8.8HIGH
vendor_ubuntu8.8HIGH
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