I think that I may have been a victim of a malicious mms I have a Sidekick 4g running Android 2.2.1.
I just received a multimedia message from an acquaintance who I happened to have in my contact list. I clicked on the notification which sent me to something that looked like a twitter login screen and then it went away and went to my home screen. I immediately turned my phone on airplane mode (in case my phone was just turned into a spam machine) and went to my messages to look at the message again, but it was gone which gives me even more fear that my phone is infected with something.
Is there a known vulnerability in android that can infect my phone without any action on my part other than viewing a message? If so, how can I eradicate it?
Edit
I do have unknown sources turned on.  I downloaded a permissions-checker app and have nothing unusual requesting to send mms, but is only beneficial if it is not a 0-day. I checked my t-mobile account and it said that I have only sent one sms this month.
TL;DR
Received mms, think my phone is now infected w/ trojan.
I had the same issue with somebody on my contact list sending me an MMS that ended up auto-extracting spyware on my phone. Long story short he was able to hear all of my calls, see all of my texts, basically was able to remotely control my phone. I would suggest a factory reset of your phone and turning your MMS auto-retrieval options to off (as it is on by default). Then change all of your passwords to your accounts that you've been using on your phone. It's a hassle but when this happened to me, I got a new phone and somehow the same symptoms carried over until I changed all of my passwords. Even now I still feel that my new phone is compromised as sometimes it will get hot for no reason or drain a lot of battery for no reason. However, it's much better than before where I would notice videos and pictures being taken remotely and once I was trying to take a selfie with a friend and my phone literally turned off by itself without a warning. I've added AV software but that didn't seem to help much. At this point use your common sense, and don't install anything from a shady third-party source. Hope this helps.