Vulnerabilities
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CVE Vulnerabilities

CVE-2020-26959

Use After Free

Published: Dec 09, 2020 | Modified: Nov 21, 2024
CVSS 3.x
8.8
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
8.8 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2020-26959
CWEhttps://cwe.mitre.org/data/definitions/416.html

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.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

NameVendorStart VersionEnd Version
FirefoxMozilla*83.0 (excluding)
Firefox_esrMozilla*78.5 (excluding)
ThunderbirdMozilla*78.5 (excluding)
Red Hat Enterprise Linux 6RedHatthunderbird-0:78.5.0-1.el6_10*
Red Hat Enterprise Linux 6RedHatfirefox-0:78.5.0-1.el6_10*
Red Hat Enterprise Linux 7RedHatthunderbird-0:78.5.0-1.el7_9*
Red Hat Enterprise Linux 7RedHatfirefox-0:78.5.0-1.el7_9*
Red Hat Enterprise Linux 8RedHatthunderbird-0:78.5.0-1.el8_3*
Red Hat Enterprise Linux 8RedHatfirefox-0:78.5.0-1.el8_3*
Red Hat Enterprise Linux 8.0 Update Services for SAP SolutionsRedHatthunderbird-0:78.5.0-1.el8_0*
Red Hat Enterprise Linux 8.0 Update Services for SAP SolutionsRedHatfirefox-0:78.5.0-1.el8_0*
Red Hat Enterprise Linux 8.1 Extended Update SupportRedHatthunderbird-0:78.5.0-1.el8_1*
Red Hat Enterprise Linux 8.1 Extended Update SupportRedHatfirefox-0:78.5.0-1.el8_1*
Red Hat Enterprise Linux 8.2 Extended Update SupportRedHatthunderbird-0:78.5.0-1.el8_2*
Red Hat Enterprise Linux 8.2 Extended Update SupportRedHatfirefox-0:78.5.0-1.el8_2*
FirefoxUbuntubionic*
FirefoxUbuntudevel*
FirefoxUbuntufocal*
FirefoxUbuntugroovy*
FirefoxUbuntuhirsute*
FirefoxUbuntuimpish*
FirefoxUbuntujammy*
FirefoxUbuntukinetic*
FirefoxUbuntulunar*
FirefoxUbuntumantic*
FirefoxUbuntunoble*
FirefoxUbuntutrusty*
FirefoxUbuntuupstream*
FirefoxUbuntuxenial*
Mozjs38Ubuntubionic*
Mozjs38Ubuntuesm-apps/bionic*
Mozjs38Ubuntuupstream*
Mozjs52Ubuntubionic*
Mozjs52Ubuntuesm-apps/focal*
Mozjs52Ubuntuesm-infra/bionic*
Mozjs52Ubuntufocal*
Mozjs52Ubuntugroovy*
Mozjs52Ubuntuupstream*
Mozjs60Ubuntuupstream*
Mozjs68Ubuntuesm-infra/focal*
Mozjs68Ubuntufocal*
Mozjs68Ubuntugroovy*
Mozjs68Ubuntuupstream*
ThunderbirdUbuntubionic*
ThunderbirdUbuntudevel*
ThunderbirdUbuntufocal*
ThunderbirdUbuntugroovy*
ThunderbirdUbuntuhirsute*
ThunderbirdUbuntuimpish*
ThunderbirdUbuntujammy*
ThunderbirdUbuntukinetic*
ThunderbirdUbuntulunar*
ThunderbirdUbuntumantic*
ThunderbirdUbuntunoble*
ThunderbirdUbuntutrusty*
ThunderbirdUbuntuupstream*
ThunderbirdUbuntuxenial*

Potential Mitigations

References

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