Cousin Domain
Cousin Domain
- April 21, 2021
- Posted by: Nicola Selenu

As commonly used a cousin domain is a domain name that is constructed in a way to fool victims into thinking it is a different, specific domain. This can be accomplished by deliberately misspelling the domain – for example, exampl3.com would be a misleading cousin domain for example.com. Fraudsters would register or gain control of exampl3.com and use it to send messages impersonating example.com, and busy or distracted users might not notice the “3” in place of the “e” and assume the message was legitimate, click on a link or open an attachment, and fall victim to the attack. In recent years it is increasingly common to see Unicode characters used to create more convincing cousin domains.
Author:Nicola Selenu
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Deliverability Glossary
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Cousin Domain
As commonly used a cousin domain is a domain name that is constructed in a way to fool victims into thinking it is a different, specific domain. This can be accomplished by deliberately misspelling the domain – for example, exampl3.com would be a misleading cousin domain for example.com. Fraudsters would register or gain control of exampl3.com and use it to send messages impersonating example.com, and busy or distracted users might not notice the “3” in place of the “e” and assume the message was legitimate, click on a link or open an attachment, and fall victim to the attack. In recent years it is increasingly common to see Unicode characters used to create more convincing cousin domains.
« Back to Glossary IndexAuthor:Nicola Selenu
Email Service Providers Handbook
The most comprehensive “Handbook of Email Service Providers“!
SPAMASSASSIN RULES
All SpamAssassin rules in one place, EXPLAINED!
SMTP COMMANDS
& REPLY CODES
All SMTP/ESMTP commands and reply codes in one place, EXPLAINED!
Free DNS Tool
Check the DNS records of your domain with our free DNS tool.
Deliverability Glossary
The most comprehensive Email Deliverability and Marketing Glossary!
« Back to Glossary Index