Vulnerabilities
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CVE Vulnerabilities

CVE-2021-38496

Use After Free

Published: Nov 03, 2021 | 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 IMPORTANT
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-2021-38496
CWEhttps://cwe.mitre.org/data/definitions/416.html

During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.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*93.0 (excluding)
FirefoxMozilla91.0 (including)91.2 (excluding)
Firefox_esrMozilla*78.15 (excluding)
ThunderbirdMozilla*78.15 (excluding)
ThunderbirdMozilla91.0 (including)91.2 (excluding)
Red Hat Enterprise Linux 7RedHatfirefox-0:91.2.0-4.el7_9*
Red Hat Enterprise Linux 7RedHatthunderbird-0:91.2.0-1.el7_9*
Red Hat Enterprise Linux 8RedHatfirefox-0:91.2.0-4.el8_4*
Red Hat Enterprise Linux 8RedHatthunderbird-0:91.2.0-1.el8_4*
Red Hat Enterprise Linux 8.1 Extended Update SupportRedHatfirefox-0:91.2.0-4.el8_1*
Red Hat Enterprise Linux 8.1 Extended Update SupportRedHatthunderbird-0:91.2.0-1.el8_1*
Red Hat Enterprise Linux 8.2 Extended Update SupportRedHatfirefox-0:91.2.0-4.el8_2*
Red Hat Enterprise Linux 8.2 Extended Update SupportRedHatthunderbird-0:91.2.0-1.el8_2*
FirefoxUbuntubionic*
FirefoxUbuntudevel*
FirefoxUbuntufocal*
FirefoxUbuntuhirsute*
FirefoxUbuntuimpish*
FirefoxUbuntujammy*
FirefoxUbuntukinetic*
FirefoxUbuntulunar*
FirefoxUbuntumantic*
FirefoxUbuntunoble*
FirefoxUbuntutrusty*
FirefoxUbuntuupstream*
FirefoxUbuntuxenial*
Mozjs38Ubuntubionic*
Mozjs38Ubuntuesm-apps/bionic*
Mozjs38Ubuntuupstream*
Mozjs52Ubuntubionic*
Mozjs52Ubuntuesm-apps/focal*
Mozjs52Ubuntuesm-infra/bionic*
Mozjs52Ubuntufocal*
Mozjs52Ubuntuupstream*
Mozjs68Ubuntuesm-infra/focal*
Mozjs68Ubuntufocal*
Mozjs68Ubuntuupstream*
Mozjs78Ubuntuesm-apps/jammy*
Mozjs78Ubuntuhirsute*
Mozjs78Ubuntuimpish*
Mozjs78Ubuntujammy*
Mozjs78Ubuntukinetic*
Mozjs78Ubuntulunar*
Mozjs78Ubuntuupstream*
ThunderbirdUbuntubionic*
ThunderbirdUbuntudevel*
ThunderbirdUbuntufocal*
ThunderbirdUbuntuhirsute*
ThunderbirdUbuntuimpish*
ThunderbirdUbuntujammy*
ThunderbirdUbuntukinetic*
ThunderbirdUbuntulunar*
ThunderbirdUbuntumantic*
ThunderbirdUbuntunoble*
ThunderbirdUbuntutrusty*
ThunderbirdUbuntuupstream*
ThunderbirdUbuntuxenial*

Potential Mitigations

References

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