Need help with USSD code and MMI on T-Mo

[b727]

Hi all,
Something very strange happened last night, my phone rang and I looked at the caller number and it showed 1;1. I called back and the screen says "USSD code running...", after a couple of seconds says "MMI complete".
I called T-Mo support and of course they don't know what I'm talking about. Has anyone experienced this?
Should I worry about Spyware?
I researched the internet for hours and no information about this.
Any help will be greatly appreciated.
My phone: Samsung GS2 running the latest official firmware.
Thanks.

 

[jdbii]

Don't know what any of that is, but I would say if your phone is running sluggish, or if it just feels like something is making it feel a bit more buggy than before you got those weird messages, then maybe I would think it might be some kind of malware or other problem with the phone's OS. Otherwise I (talking about myself) wouldn't be too worried about it.

 

[xKrNMBoYx]

USSD Codes are a set of numbers and symbols entered into the dialpad of a smartphone (most Samsung). Each set of codes have a specific thing they do. I can't really explain it so I'll post a few links about them. You have to becareful with these codes. Last year there was that rave about the USSD codes that could be run by clicking on a bad link set up by a hacker that could reset your whole phone. A connection can be made between two devices with some codes. To be safe I would install a virus/malaware scanner and try a system scan of your phone. If it keeps on running sluggish you should probably reset your phone anyway.

[REF] List of USSD codes! [Updated 10-30] - xda-developers
Unstructured Supplementary Service Data - Wikipedia, the free encyclopedia