Sony Corp has hired a former official from the US Department of Homeland Security as their chief information security officer. The move comes after Sony was the target of a devastating cyber attack earlier this year that subsequently caused shares in the company to fall 55 percent, according to Reuters.

Philip Reitinger is the former head of the US National Cyber Security Center for the Department of Homeland Security and will now be in charge of keeping Sony's network, and more importantly, user's personal data safe from further attacks. A Sony spokesperson said that the network issue was a catalyst for the appointment and that the company is looking to bolster security even further.

In early April, the hacker group Anonymous executed a distributed denial of service (DDoS) attack against the Sony Playstation website. Later that month, between April 17 and 19, the Playstation Network was hacked and certain PSN and Qriocity account details were compromised. Sony pulled the plug on those networks and hired an external security firm to perform a complete investigation.

The outage lasted for roughly three weeks and cost Sony nearly $175 million. Over 100 million accounts are thought to have been compromised in the attacks. In response to angry customers, Sony offered all affected users two free PS3 or PSP games of their choice as well as a selection of free movie rentals for one weekend and a free month's subscription to Playstation Plus for non-subscribers (or an extension of 60 days for existing members).