cbcvebase.
CVE-2021-23987
published 2021-03-31

CVE-2021-23987: Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. Some of these bugs showed evidence of memory…

PriorityP343high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
1.40%
69.2th percentile
Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. 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 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

nvdv3.18.8HIGHCVSS: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_ubuntu8.1HIGH
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