Sony has simply blamed the ongoing PSN outage on an “external intrusion” without going into the exact cause and nature of this unrelenting crisis - equal parts technical disaster and public relations fiasco. According to a Redditor named chesh420, who only identified himself as a PSX-Scene.com moderator, the
current PSN outage could be the result of a new custom firmware (CFW) named Rebug
that “essentially turns a retail console into a dev console (not fully, but gives you a lot of the same options that usually dev's only have access to).”
Soon after its launch on March 31, 2011, CFW users began using Rebug to get their hacked consoles back onto PSN. But the real problem began when some people discovered that Rebug also enabled them to download PSN content using fake credit card information. Apparently, Sony did not feel the need of authenticating credit card information sent over its private developer network.
“What happened next was extreme piracy of PSN content. Sony realizing the issue here shut down the network.,” wrote chesh420 in a post on Reddit. However, he later reminded everyone to take his explanation of the outage with a grain of salt as, no matter how reasonable, “this is all speculation and information gathered from various devs in the PS3 scene.”