Wi-Fi is as secure as your virginity in the Zone, in Old Taipei - Charles Brown
Apparently a buffer overflow problem means that malicious code can be run on the PSP. To do it the hacker would have to come up with some code, but a proof of concept that exploits the flaw by using .tiff files has been spotted in the wild.
A spokesPanda said the flaw was dangerous and could make the PSP vulnerable to a Trojan attack.
He warned that PSP owners should not install software that does not come from reliable sources on consoles also they should be careful about letting any Tom, Dick, or Harry connecting to their machine.
More here. µ