cbcvebase.
CVE-2021-43534
published 2021-12-08

CVE-2021-43534: Mozilla developers and community members reported memory safety bugs present in Firefox 93 and Firefox ESR 91.2. Some of these bugs showed evidence of memory…

PriorityP342high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
1.21%
64.6th percentile
Mozilla developers and community members reported memory safety bugs present in Firefox 93 and Firefox ESR 91.2. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Affected

19 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianfirefox< firefox 94.0-1 (sid)firefox 94.0-1 (sid)
debianfirefox-esr< firefox 94.0-1 (sid)firefox 94.0-1 (sid)
debianthunderbird< firefox 94.0-1 (sid)firefox 94.0-1 (sid)
mozillafirefox< 94.094.0
mozillafirefox
mozillafirefox>= unspecified < 9494
mozillafirefox_esr< 91.3.091.3.0
mozillafirefox_esr>= unspecified < 91.391.3
mozillathunderbird< 91.3.091.3.0
mozillathunderbird>= 0 < 1:91.4.1-1~deb11u11:91.4.1-1~deb11u1
mozillathunderbird>= 0 < 1:91.3.0-11:91.3.0-1
mozillathunderbird>= 0 < 1:91.3.0-11:91.3.0-1
mozillathunderbird>= 0 < 1:91.3.0-11:91.3.0-1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.18.04.11:91.5.0+build1-0ubuntu0.18.04.1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.20.04.11:91.5.0+build1-0ubuntu0.20.04.1
mozillathunderbird>= unspecified < 91.391.3

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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