cbcvebase.
CVE-2021-23995
published 2021-06-24

CVE-2021-23995: When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been…

PriorityP344high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
1.21%
64.8th percentile
When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been exploited to run arbitrary code. 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
nvdv2.05.1MEDIUMAV:N/AC:H/Au:N/C:P/I:P/A:P
osv8.8HIGH
vendor_debian8.8HIGH
vendor_redhat8.8HIGH
vendor_ubuntu8.8HIGH
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