Microsoft's Xbox Live also suffered a disruption on Christmas Day, but it was back up and running on Friday, although some individual applications are still down, according to the service's status page. Microsoft has acknowledged Xbox Live suffered a service disruption but hasn't disclosed the cause.
The Lizard Squad hacker group claimed responsibility on Christmas Day for the outages that hit PlayStation Network and Xbox Live, saying it had launched successful DDoS attacks against the two online gaming platforms.
However, on Friday the group said via its Twitter account that it had stopped the DDoS attacks and turned its attention to Tor, a service that lets users surf the web, post content online and engage in Internet communications anonymously.
"To clarify, we are no longer attacking PSN or Xbox. We are testing our new Tor 0day," Lizard Squad tweeted, a message it reiterated Saturday.
Late on Friday, Tor put out a statement confirming its service was under fire, and described the action as a "Sybil attack."
"The attackers have signed up many new relays in hopes of becoming a large fraction of the network. But even though they are running thousands of new relays, their relays currently make up less than 1% of the Tor network by capacity," Tor's statement reads.
Tor said it was working to remove the relays from its network, and that it didn't expect "any anonymity or performance effects" on its service, which so far doesn't seem to have been disrupted.
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