How severe is CVE-2021-38597?

CVE-2021-38597 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-38597 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38597?

CVE-2021-38597 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-38597?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-38597 published?

CVE-2021-38597 was published on 2021-08-12 and last updated on 2026-06-17.

CVE-2021-38597

CVE-2021-38597 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 5.9. 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-345.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-345
Affected product: Wolfssl
Published: 2021-08-12
Last modified: 2026-06-17

Description

wolfSSL before 4.8.1 incorrectly skips OCSP verification in certain situations of irrelevant response data that contains the NoCheck extension.

Frequently asked questions

What is CVE-2021-38597?: wolfSSL before 4.8.1 incorrectly skips OCSP verification in certain situations of irrelevant response data that contains the NoCheck extension.
How severe is CVE-2021-38597?: CVE-2021-38597 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-38597 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38597?: CVE-2021-38597 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-38597?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38597 published?: CVE-2021-38597 was published on 2021-08-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

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