Here is some documentation around how we can mask the password from selenium in ASM. It’s just adding a line to the selenium script that is storing the password in a variable. When it gets uploaded to ASM if the user does not have Check Admin rights, they will not be able to Edit the check and thus will not be able to see the password. However, any user that is a Check Admin, will be able to Edit the check and consequently be able to see the password. Below are a few screenshots:
http://academy.apicasystems.com/asmdocs/kb/tech/selenium/mask/start

Check Admin Role enabled: User can click this button and will be able to see the password

Check Admin Role NOT enabled: User will NOT have the option to edit the check and will not be able to see the password.

Let me know if you want some help setting up a script or if you have any questions about this. Thanks!