Cousins domains can be created and used to spoof both the sender and the URL. With this technique hackers will remove letters or alternate the spellings to a registered domain name, so it looks deceptively similar to a target name. Here’s an example of a real address versus a spoofed address:
Real address: [email protected]
Spoofed address: [email protected]
Since we as users tend to read domain names quickly, it’s hard to tell that an “s” was removed in the spoofed address.