CVE-2021-20308

Integer overflow in the htmldoc 1.9.11 and before may allow attackers ...

Published 5 Apr 2021Modified 17 Jun 2026CWE 190

In the Trivy database since at least 24 Oct 2026, 07:11 UTCWhen it arrived before that build is not recorded.

Severity by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Trivy's own label is CRITICAL. Rated critical by NVD. Rated lower by Ubuntu (medium).

Description

Integer overflow in the htmldoc 1.9.11 and before may allow attackers to execute arbitrary code and cause a denial of service that is similar to CVE-2017-9181.

Affected packages and fixed versions

Source	Package	Fixed in
debian 10	htmldoc	1.9.3-1+deb10u1
debian 11	htmldoc	1.9.11-3
debian 12	htmldoc	1.9.11-3
debian 13	htmldoc	1.9.11-3
debian 14	htmldoc	1.9.11-3
debian 9	htmldoc	1.8.27-8+deb9u1
echo	htmldoc	1.9.11-3
ubuntu 16.04-ESM	htmldoc	1.8.27-8ubuntu1.1+esm2
ubuntu 18.04-ESM	htmldoc	1.9.2-1ubuntu0.2+esm1
ubuntu 20.04-ESM	htmldoc	1.9.7-1ubuntu0.3+esm1

References

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Vulnerability data compiled from the Trivy vulnerability database (trivy-db, Aqua Security, Apache License 2.0), which aggregates third-party advisories. CVE records are published by The MITRE Corporation under the CVE Terms of Use; CVE is a trademark of MITRE. This product uses data from the NVD API but is not endorsed or certified by the NVD. Severity, titles and advisory data from the GitHub Advisory Database (CC BY 4.0), Red Hat security data (CC BY 4.0) and the other sources linked on each entry. Entries may be summarised or re-formatted; the linked original is the authoritative record.