Block fake sender

Question

How can I block in the ESA config, the the outside not trusted server with my domain. 
 
 Example: 
 https://emkei.cz/ 
 Send this form myaddress@mydomain.hu to myaddress@mydomain.hu and I recived. 
 
 Or mail header 
 To: "fake@fake.net" <fake@fake.net> but envelope-from is myaddress@mydomain.hu and I recived.

AimanAnsari · Accepted Answer

Hello Zsolt, 
 Greetings. 
 Refer below article to block spoofed senders. 
 ----------------------------------------- Article ID:118845 Title:Sophos Email Appliance: Dealing with spoofed sender addresses URL: http://sophos.com/kb/118845 ----------------------------------------- 
 Let me know if you have any further questions. 
 
 Regards,