CVE Vulnerabilities

CVE-2021-33391

Use After Free

Published: Feb 17, 2023 | Modified: Mar 18, 2025
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM
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An issue in HTACG HTML Tidy v5.7.28 allows attacker to execute arbitrary code via the -g option of the CleanNode() function in gdoc.c.

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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.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
TidyHtacg5.7.28 (including)5.7.28 (including)
Tidy-html5Ubuntubionic*
Tidy-html5Ubuntudevel*
Tidy-html5Ubuntuesm-infra/bionic*
Tidy-html5Ubuntuesm-infra/focal*
Tidy-html5Ubuntufocal*
Tidy-html5Ubuntujammy*
Tidy-html5Ubuntukinetic*
Tidy-html5Ubuntulunar*
Tidy-html5Ubuntumantic*
Tidy-html5Ubuntunoble*
Tidy-html5Ubuntuoracular*
Tidy-html5Ubuntuplucky*
Tidy-html5Ubuntuquesting*
Tidy-html5Ubuntutrusty*
Tidy-html5Ubuntuxenial*

Potential Mitigations

References