The encoded format of X25519 and X448 private keys has been corrected to use the standard format described in RFC 8410. This change affects any private key produced from the "X25519", "X448", or "XDH" services in the SunEC provider. The correct format is not compatible with the format used in previous JDK versions. It is recommended that existing incompatible keys in storage be replaced with newly-generated private keys.