CVE-2021-33391
CVSS v3
9.8
CRITICAL
EPSS Score
1.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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.
Technical details
- Published
- 2023-02-17
Frequently asked questions
What is CVE-2021-33391?
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.
Is CVE-2021-33391 actively exploited?
Active exploitation of CVE-2021-33391 has not been confirmed. Its EPSS score was 1.1% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-33391?
CVE-2021-33391 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-33391 affecting your environment?
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