CVE-2021-33391

CRITICAL 9.8CVE-2021-33391 · Published 17/02/2023 · updated 17/06/2026

In short

CVE-2021-33391 is a CRITICAL (CVSS 9.8) vulnerability affecting tidy (htacg).
Chance of exploitation in the next 30 days (EPSS): 1.1%, higher than 66.5% of all vulnerabilities.
No patched version is listed yet: follow the vendor's advisory in References.

Package	Affected versions	Patched versions
tidy htacg	`= 5.7.28`	No fix yet

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.

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