What can class 0 message (flash SMS) do to Android devices? I'm using a Samsung phone and I recently got an anonymous message via Class 0 Message 




  Class 0 Message
  
  URGENT MATTER ,CONTACT
  ME MY EMAIL NOW
  (email redacted)
  
  From: (phone no. redacted)


I saw a concerning article regarding the issue, it said that it can apparently reboot your phone? Is that true?

What I did was I responded to the email not knowing it might be a scam.
Try to install a good antivirus, on Google there are free good antivirus like AVG, Avast and the like. Then, try to full scan on your device looking for some malware and don't forget to full scan the sdcard too.
If after made the step 1 succesfully you still are getting that SMS message, so I highly recommend you to factory reset your device, which one means that your device go back to the factory settings and all the data stored on the device will be deleted except the sdcard data (of course, if you didn't encrypt the sdcard).


Important: if you factory reseted your device, pay much attention when installing apps again, check out apps are really trusted.

References:


The best antivirus software for
Android
Don't Answer Text Messages of This Type. It May Be a
Scam
Malware
How to factory reset Android
devices