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Understanding the Christmas Attacks on Xbox, PlayStation Networks

What is a "denial of service" attack, and what's the point?

If you unwrapped a new Xbox or PlayStation game console on Christmas, you probably know by now that Microsoft’s and Sony’s respective online networks have been struggling since yesterday morning.

These “denial of service” attacks are not only a problem for people who want to play a multiplayer game online. They also affect anyone trying to register a new account, buy games or use media apps to stream movies and music from the Web. Unlike the recent more sophisticated hack attack at Sony Pictures, the goal appears to be to cause mayhem and headaches for Microsoft and Sony rather than to steal private data or achieve a political goal.

At the time of this writing, Xbox Live is back “up and running” while the PlayStation Network is still “offline.” But what causes this sort of downtime, and why?

It might help to understand what a “denial of service” attack is. I asked cybersecurity researcher Cameron Camp to explain back in August when an anonymous online hacking group called Lizard Squad first targeted PlayStation:

“At the most basic level, it’d be like someone calling your phone 2,800 times and you’re going, ‘Leave me alone, leave me alone, leave me alone,'” Camp said. “When they’re flooding your phone, you can’t get other phone calls. The idea is, what if we could trick other computers into all robot-calling your phone? Now you really can’t take a phone call.”

To “weaponize” this sort of attack, Camp said, hackers can pay to rent computers that have been infected with malware and point them at the same target. Companies like Microsoft and Sony then have to find ways to weed out the bad “phone calls,” often by paying a third-party company to accept all the rerouted requests, filter them and route only the good ones back to the source.

Denial of service attacks are, like a rock thrown through a window, unsophisticated but effective at causing a mess. Unlike the supposedly politically motivated attack on Sony Pictures (which the FBI pinned on North Korea), the closest apparent thing to a goal here is temporary cyber-anarchy.

As in August and in other attacks since, Lizard Squad has taken credit for the downtime on both consoles. In tandem with one of its earlier attacks on the PlayStation Network, the group tweeted a bogus bomb threat against an airplane carrying a Sony executive.

In a strange twist to the latest attacks, Mega founder Kim Dotcom is taking credit for helping to stop them. In order to play the online shooter game Destiny on Xbox Live, he claims to have transferred 3000 premium vouchers to his latest cloud storage website to the hacker group, which thanked him and said it would stop.

I’ve reached out to Sony for further comment. A Microsoft spokesperson shared the following statement:

“Yesterday, some users were unable to sign in to Xbox Live. Our teams worked throughout the holiday to resolve the issue, and Xbox Live core services have now been restored.”

This article originally appeared on

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