How severe is CVE-2021-20232?

CVE-2021-20232 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20232 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20232?

CVE-2021-20232 primarily affects Redhat Enterprise Linux. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20232?

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

When was CVE-2021-20232 published?

CVE-2021-20232 was published on 2021-03-12 and last updated on 2026-06-17.

CVE-2021-20232

CVE-2021-20232 is a critical-severity vulnerability in Redhat Enterprise Linux with a CVSS 3.x base score of 9.8. 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-416.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Redhat Enterprise Linux
Published: 2021-03-12
Last modified: 2026-06-17

Description

A flaw was found in gnutls. A use after free issue in client_send_params in lib/ext/pre_shared_key.c may lead to memory corruption and other potential consequences.

Frequently asked questions

What is CVE-2021-20232?: A flaw was found in gnutls. A use after free issue in client_send_params in lib/ext/pre_shared_key.c may lead to memory corruption and other potential consequences.
How severe is CVE-2021-20232?: CVE-2021-20232 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20232 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20232?: CVE-2021-20232 primarily affects Redhat Enterprise Linux. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20232?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-20232 published?: CVE-2021-20232 was published on 2021-03-12 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

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