What is CVE-2021-23180?

CVE-2021-23180 is a high-severity vulnerability in Htmldoc Project, classified under NULL Pointer Dereference. CVSS score: 7.8/10. Published 2022-03-02.

How severe is CVE-2021-23180?

High severity. CVSS v3 base score is 7.8 out of 10.

NULL pointer dereference in Htmldoc Project

CVE-2021-23180

A flaw was found in htmldoc in v1.9.12 and before. Null pointer dereference in file_extension(),in file.c may lead to execute arbitrary code and denial of service.

Published 2022-03-02 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.014 (70.5th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 70.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Htmldoc Project
Htmldoc — versions Fixed in htmldoc v1.9.12 and above.

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

References

github.com/michaelrsweet/htmldoc/issues/418 (Exploit, Third Party Advisory, Issue Tracking)
bugzilla.redhat.com/show_bug.cgi (Patch, Third Party Advisory, Issue Tracking)
ubuntu.com/security/CVE-2021-23180 (Third Party Advisory)
github.com/michaelrsweet/htmldoc/commit/19c582fb32eac74b57e155cffbb529377a9e751a (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-23180?: CVE-2021-23180 is a high-severity vulnerability in Htmldoc Project, classified under NULL Pointer Dereference. CVSS score: 7.8/10. Published 2022-03-02.
How severe is CVE-2021-23180?: High severity. CVSS v3 base score is 7.8 out of 10.