CVE-2021-37155

CRITICALNVD 9.89.8—

9.8

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.

CVSS v3: 9.8
EG Score: 9.8(medium)
EPSS: 66.9%
KEV: Not listed

Published

July 21, 2021

Last Modified

November 21, 2024

Advisory Details (2)

Auto-updated May 26, 2026

Patch available. Sources: github_release, github_pr.

github_release Patch Available

wolfSSL release version 4.8.0

Patch available: wolfSSL/wolfssl v4.8.0-stable

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

github_pr

Fix CompareOcspReqResp.

Fix merged in wolfSSL/wolfssl PR #3990 on 2021-04-28 — awaiting tagged release

https://github.com/wolfSSL/wolfssl/pull/3990

Data Freshness Timeline

(refreshed 12× in last 7d / 20× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

2026-06-08 14:15 UTCEPSS rescore
2026-06-08 14:15 UTCEPSS rescore
2026-06-07 15:23 UTCEPSS rescore
2026-06-07 15:23 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-05 22:45 UTCEPSS rescore
2026-06-05 06:09 UTCEPSS rescore
2026-06-05 06:09 UTCEPSS rescore
2026-06-04 13:10 UTCEPSS rescore
2026-06-04 13:10 UTCEPSS rescore
2026-06-02 20:11 UTCEPSS rescore
2026-06-02 20:11 UTCEPSS rescore
2026-06-01 13:50 UTCEPSS rescore
2026-06-01 13:50 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 00:15 UTCEPSS rescore
2026-05-31 00:15 UTCEPSS rescore

Frequently asked(5)

What is CVE-2021-37155?

CVE-2021-37155 is a critical vulnerability published on July 21, 2021. 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.

When was CVE-2021-37155 disclosed?

CVE-2021-37155 was first published in the National Vulnerability Database on July 21, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-37155 actively exploited?

CVE-2021-37155 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 66.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-37155?

CVE-2021-37155 has a CVSS v3 base score of 9.8 (NVD).

How do I remediate CVE-2021-37155?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-37155, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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