<PackageReference Include="BouncyCastle.Cryptography" Version="2.5.1" />

Org.BouncyCastle.Crypto.InvalidCipherTextException

This exception is thrown whenever we find something we don't expect in a message.
namespace Org.BouncyCastle.Crypto { public class InvalidCipherTextException : CryptoException { public InvalidCipherTextException(); public InvalidCipherTextException(string message); public InvalidCipherTextException(string message, Exception innerException); protected InvalidCipherTextException(SerializationInfo info, StreamingContext context); } }