We have just released Go versions 1.16.6 and 1.15.14, minor point releases.
These minor releases include a security fix according to the new security policy (#44918
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.
This is issue #47143
and CVE-2021-34558. Thanks to Imre Rad for reporting this issue.
Dmitri, Filippo, and Alex for the Go team