CVE-2026-89136: Client accepts unsolicited RawPublicKey server certificate type
When using RPK (Raw Public Key), the client side of a TLS 1.2, 1.3 and DTLS 1.2 connection could accept an unsolicited servercerttype=RawPublicKey which allowed a malicious or misbehaving server to bypass authentication. RPK is off by default and only enabled in --enable-rpk OR --enable-all OR --enable-distro AKA HAVERPK builds.
Affected Software
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Only wolfSSL client deployments with Raw Public Key support enabled are exposed. RPK is off by default and is enabled only in builds configured with --enable-rpk, --enable-all, or --enable-distro (HAVE_RPK).
What does an attacker need to exploit this?
An attacker needs to act as, or control, a malicious or misbehaving TLS 1.2, TLS 1.3, or DTLS 1.2 server during a client connection. The issue involves the server sending an unsolicited server_cert_type=RawPublicKey.
What is the security impact for an affected client?
An affected client can accept the unsolicited RawPublicKey server certificate type, allowing the server to bypass authentication.