CVE-2021-20308
CVSS v3
9.8
CRITICAL
EPSS Score
2.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2021-04-05
Frequently asked questions
What is CVE-2021-20308?
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.
Is CVE-2021-20308 actively exploited?
Active exploitation of CVE-2021-20308 has not been confirmed. Its EPSS score was 2.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-20308?
CVE-2021-20308 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-20308 affecting your environment?
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