cbcvebase.
CVE-2020-26959
published 2020-12-09

CVE-2020-26959: During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a…

PriorityP340high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
1.27%
66.4th percentile
During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Affected

12 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 83.0-1 (sid)firefox 83.0-1 (sid)
debianfirefox-esr< firefox 83.0-1 (sid)firefox 83.0-1 (sid)
debianthunderbird< firefox 83.0-1 (sid)firefox 83.0-1 (sid)
mozillafirefox< 8383
mozillafirefox< 83.083.0
mozillafirefox
mozillafirefox_esr< 78.578.5
mozillathunderbird< 78.578.5
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1
mozillathunderbird>= 0 < 1:78.5.0-11:78.5.0-1

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
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