OSEC-2026-06 TLS-client (with TLS 1.3) does insufficient certificate checks (missing KeyUsage and ExtendedKeyUsage validation)

The ocaml-TLS 1.3 client does not validate the KeyUsage and ExtendedKeyUsage extensions of the server certificate. This can lead to impersonation with a certificate issued to a client. Scenario Every employee at a major bank carries a smart card. The card holds a clientAuth certificate issued by...