CVE-2026-5501

wolfSSL_X509_verify_cert in the OpenSSL compatibility layer accepts a certificate chain in which the leaf's signature is not checked, if the attacker supplies an untrusted intermediate with Basic Constraints `CA:FALSE` that is legitimately signed by a trusted root. An attacker who obtains any leaf certificate from a trusted CA (e.g. a free DV cert from Let's Encrypt) can forge a certificate for any subject name with any public key and arbitrary signature bytes, and the function returns `WOLFSSL_SUCCESS` / `X509_V_OK`. The native wolfSSL TLS handshake path (`ProcessPeerCerts`) is not susceptible and the issue is limited to applications using the OpenSSL compatibility API directly, which would include integrations of wolfSSL into nginx and haproxy.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10102	Issue Tracking

Configurations

Configuration 1 (hide)

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

History

27 Apr 2026, 17:57

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.1
References	~~() https://github.com/wolfSSL/wolfssl/pull/10102 -~~	() https://github.com/wolfSSL/wolfssl/pull/10102 - Issue Tracking
First Time		Wolfssl Wolfssl wolfssl
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::

10 Apr 2026, 04:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-10 04:17

Updated : 2026-04-27 17:57

NVD link : CVE-2026-5501

Mitre link : CVE-2026-5501

CVE.ORG link : CVE-2026-5501

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-295

Improper Certificate Validation

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