CVE-2021-20231
CVSS v3
9.8
CRITICAL
EPSS Score
3.8 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
A flaw was found in gnutls. A use after free issue in client sending key_share extension may lead to memory corruption and other consequences.
Technical details
- Published
- 2021-03-12
Frequently asked questions
What is CVE-2021-20231?
A flaw was found in gnutls. A use after free issue in client sending key_share extension may lead to memory corruption and other consequences.
Is CVE-2021-20231 actively exploited?
Active exploitation of CVE-2021-20231 has not been confirmed. Its EPSS score was 3.8% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-20231?
CVE-2021-20231 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-20231 affecting your environment?
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