Don't follow this stuff much anymore. Historically speaking, there's also been a bunch of vulnerabilities in various TCP/IP stacks. By sending a valid or malformed packet that the stack does not handle correctly you have been able infect the machine. Any one remember the Windows 95/98/ME MSG_OOB bug, or NT teardrop?

Remembering them, some years ago, while implementing Ethernet drivers, I replicated and patched the exact same MSG_OOB vulnerability on a LwIP stack. i.e. completely unrelated/different OS many years later and IP stack same issue.
You could literally kill the whole stack and "make stuff happen" with a PING.

All one had to do was to tag the IMCP packet MSG_OOB, and put data inside the ping. 

So yes, maybe your phone has been hacked with a ping.