In October of 2017, MyHeritage suffered a data breach. Over 92 million customer records were exposed. This included email addresses and salted SHA-1 password hashes.
Since then, attackers have been able to crack majority of the password hashes. The list of email address and cracked passwords from the MyHeritage breach has recently come up for sale on the Dark Web.
How does this affect me?
Password reuse: Many people make the mistake of using the same password over many – or on all websites.
If you have used the same password for MyHeritage as you do for Email, Facebook, Banking, etc. An attacker can use this information to access those accounts.
What do I need to do?
Identify any service where you may have used the same password, and then request a password change. This can be done via the ‘forgot my password’ link on most websites.
Set the new password to something secure and unique. Write this down in a notebook stored securely at home, or better, use a password manager.
Another important step in keeping secure is to use Two-Factor Authentication.
Check if you have been ‘Pwned’
HaveIBeenPwned.com is a service that allows you to see if your email or password has been seen in any data breaches where data has become public.
You can check your email at: https://haveibeenpwned.com/
You can check a password at: https://haveibeenpwned.com/Passwordss
I highly recommend you use this free service to help keep yourself secure.
What is salted and hashed?
When you sign up to a website you are required to enter a password. The password is then converted to a hash and stored in a database.
When you log into a website, the password is converted to a hash and compared with the stored hash. If they match, you are able to log in.
If your password is grenfell, and the website is using a SHA1 hashing algorithm (as was the case with MyHeritage), it will convert the text to 3EC63D4F11F08C81B448F922A316E44E0F1628E0
This is to help slow an attacker down that may have breached the service – but it is not impossible to reverse.
Using a password cracking program called Hashcat. I was able to reverse the SHA1 hash for grenfell in under a second. This was using a brute force on all lowercase letters and numbers.
A salted SHA1 hash looks a little different. Before a password hash is created a salt is added to the password.
If your password was grenfell, and the salt was 2019, the hash would be CEE02FF760DA4C0F8887AFDFA70EEF8AE1B70BC6
You can see the difference in the hashes for the same passwords. If done correctly, each users password will have a unique salt. This means users sharing the same password will still have unique password hashes.
Because the salt was known in my example, the password can also be cracked in under a second.
The attackers who have cracked the MyHeritage password hashes have been able to do some by discovering the salt that was used. and then using this information to crack the passwords.
In cases like this, simple passwords are the first that get ‘cracked’. Of the 92,283,889 accounts that were breached on MyHeritage, 91,991,358 were eventually cracked.
This potentially means 292,531 users were using passwords strong enough to withstand the cracking attempts. Using strong passwords will help you to be in this group of people.