CVE-2021-37155

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-07-21 · updated 2026-06-17

Description

wolfSSL 4.6.x through 4.7.x before 4.8.0 does not produce a failure outcome when the serial number in an OCSP request differs from the serial number in the OCSP response.

Affected products

wolfSSL: from 4.6.0 before 4.8.0 — fixed in 4.8.0

How to fix

Upgrade to a fixed version: wolfSSL 4.8.0. Check the vendor advisory for mitigations.

References

https://github.com/wolfSSL/wolfssl/pull/3990
https://github.com/wolfSSL/wolfssl/releases/tag/v4.8.0-stable
https://github.com/wolfSSL/wolfssl/pull/3990
https://github.com/wolfSSL/wolfssl/releases/tag/v4.8.0-stable

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