There are reports of Malware in the PS Vita Piracy scene. When you have to pursue shady enterprises to use the hardware you own this is always the risk you take. Consoles have the coolest security hardware, but it is aimed at stopping piracy rather than protecting users.
The Grey area jailbreak tools live in make it really hard for users to find the real tools. Instead the end up with malware.
Here is 50 minutes on why this was going to happen.
Reading: The Puzzle Palace