What is CVE-2026-55964?

CVE-2026-55964 is a medium-severity vulnerability in Wolfssl, classified under Improper Certificate Validation. CVSS score: 5.3/10. Published 2026-06-25.

How severe is CVE-2026-55964?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Wolfssl

CVE-2026-55964

Chain intermediate CA:TRUE without keyCertSign accepted as a signing CA. Intermediate CA certificates are required to have the keyCertSign key usage when a Key Usage extension is present, but chain-supplied temporary CAs (WOLFSSL_TEMP_CA)…

Vulnerability class: Improper Certificate Validation

EPSS: 0.001 (2.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

Affected products

Wolfssl — versions 5.7.4

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

facts@wolfssl.com (Patch, patch, Issue Tracking)
facts@wolfssl.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-55964?: CVE-2026-55964 is a medium-severity vulnerability in Wolfssl, classified under Improper Certificate Validation. CVSS score: 5.3/10. Published 2026-06-25.
How severe is CVE-2026-55964?: Medium severity. CVSS v3 base score is 5.3 out of 10.