A text from appleid.alert@icloud.com came in?

It was asking for my PW for security reasons due to an unknown device trying to log in. I don't recall giving out my apple ID nor my password to anyone, so I thought this was sketchy. The text said my account will be suspended if I dont respond. Is this spam? I wrote back saying "spam" and it said "Incorrect password. Please try again." Has anyone ever gotten this text before? Yes, in iMessage form. Not an e-mail.