crypto/tls clients can panic when provided a certificate of the wrong type for the negotiated parameters. net/http clients performing HTTPS requests are also affected. The panic can be triggered by an attacker in a privileged network position without access to the server certificate's private key, as long as a trusted ECDSA or Ed25519 certificate for the server exists (or can be issued), or the client is configured with Config.InsecureSkipVerify. Clients that disable all TLS_RSA cipher suites (that is, TLS 1.0–1.2 cipher suites without ECDHE), as well as TLS 1.3-only clients, are unaffected.
Thanks to Imre Rad for reporting this issue.
This issue is CVE-2021-34558.
crypto/tlsclients can panic when provided a certificate of the wrong type for the negotiated parameters.net/httpclients performing HTTPS requests are also affected. The panic can be triggered by an attacker in a privileged network position without access to the server certificate's private key, as long as a trusted ECDSA or Ed25519 certificate for the server exists (or can be issued), or the client is configured withConfig.InsecureSkipVerify. Clients that disable allTLS_RSAcipher suites (that is, TLS 1.0–1.2 cipher suites without ECDHE), as well as TLS 1.3-only clients, are unaffected.Thanks to Imre Rad for reporting this issue.
This issue is CVE-2021-34558.