Twice in the last three days my S4 on 5.0.1 has been displaying a text message that appears to be from (I don't recall a message)
WAP_PUSH_SI! and then the message is blank and difficult to delete.
I've no idea where it's come from, I'd been in Oz for a week, but no new apps, and my phone has been doing quite a few auto updates in the last 48 hours. Which is normal, I'm often away from wifi during the week, so normally the apps will update once I'm home. I've got no idea what this is, or whether it's something sinister or not.
This is how it appears in my inbox. I don't actually text much anymore, just a handful of contacts really.