Mail-Hash
Chrome Extension that adds a random hash to any plus addressable email address or prepends a custom domain. Please use it in combination with a password manager.
Freely available to download here.
Demo (Youtube)
Why?
Email providers that support plus addressing or tagging enable you to append something to your address and still receive it in your normal inbox. Let's say your email address is your.name@gmail.com. You sign up on facebook with the your.name+facebook@gmail.com. All emails from facebook will still reach your inbox. You can simply block any emails to your.name+facebook@gmail.com and still receive all emails sent to your.name@gmail.com.
Let's say a service get's hacked and your credentials wind up in a database like have i been pwned?
When you use plus tags such as facebook or twitter or servicename it's pretty easy for an attacker to still determine your email address for another service and try to get in with the leaked passwords.
Mail hash adds a random hash to your mail address!
your.name@gmail.com --> your.name+6as6d7@gmail.com
your-domain.com --> ZpGM5rrfZ6@your-domain.com
each time you hit the button.
Your hashed email address becomes part of the key you use to access and login to a service.
Attackers can't easily reuse the credentials for brute force attacks on other services if you use a differnt hash every time.
Credit
This was inspired by this tweet by @levelsio