Medium severity · published Aug 12, 2021
CVE-2021-38597
wolfSSL before 4.8.1 incorrectly skips OCSP verification in certain situations of irrelevant response data that contains the NoCheck extension
5.9
CVSS
0.5%
EPSS
No
On KEV
Description
wolfSSL before 4.8.1 incorrectly skips OCSP verification in certain situations of irrelevant response data that contains the NoCheck extension.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WO
Wolfssl · Wolfssl
before 4.8.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-38597
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-38597
Patch
https://github.com/wolfSSL/wolfssl/commit/f93083be72a3b3d956b52a7ec13f307a27b6e093
Release Notes
https://www.wolfssl.com/docs/wolfssl-changelog/
More from Wolfssl
9.8
CVE-2026-7531
Use-after-free in PQC hybrid key-share handling
9.8
CVE-2026-5264
DTLS 1.3 ACK heap buffer overflow
9.8
CVE-2026-5187
Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL
9.8
CVE-2026-4395
Heap-based buffer overflow in wc_ecc_import_x963_ex KCAPI path
9.8
CVE-2026-3849
Buffer Overflow in HPKE via Oversized ECH Config