It is important that your CRA account has a unique password that you do not use on any other accounts or devices.
If one or more of the following apply, it may be time for you to change your password:
You use the same password on another website, account or device
Your password contains personal information
You have shared your password with someone else
The CRA account sign-in credential allows up to 64 characters to ensure that you can create stronger passwords and protect your account.
Click here to learn more.
Information source from Canada Revenue Agency (CRA)