How severe is CVE-2021-23191?

CVE-2021-23191 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-23191 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23191?

CVE-2021-23191 affects Htmldoc Project Htmldoc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23191?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-23191 published?

CVE-2021-23191 was published on 2022-03-02 and last updated on 2026-06-17.

CVE-2021-23191

CVE-2021-23191 is a high-severity vulnerability in Htmldoc Project Htmldoc with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Htmldoc Project Htmldoc
Published: 2022-03-02
Last modified: 2026-06-17

Description

A security issue was found in htmldoc v1.9.12 and before. A NULL pointer dereference in the function image_load_jpeg() in image.cxx may result in denial of service.

Frequently asked questions

What is CVE-2021-23191?: A security issue was found in htmldoc v1.9.12 and before. A NULL pointer dereference in the function image_load_jpeg() in image.cxx may result in denial of service.
How severe is CVE-2021-23191?: CVE-2021-23191 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-23191 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23191?: CVE-2021-23191 affects Htmldoc Project Htmldoc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23191?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-23191 published?: CVE-2021-23191 was published on 2022-03-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:htmldoc_project:htmldoc:*:*:*:*:*:*:*:*

More vulnerabilities in Htmldoc Project Htmldoc

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