Coding Website Says an Attack, Probably by China, Has Ended

GitHub, a site that hosts code for programmers, said on Tuesday that a major attack, which seemed to come from the Chinese government, had subsided.

For nearly five days, GitHub was overwhelmed by traffic that security experts said originated from the Great Firewall, a term used to describe China's Internet censorship mechanisms. The attack was a change in the behavior of the filters that block Chinese Internet users from viewing foreign websites deemed sensitive or destabilizing.

Instead of simply blocking sites, the Great Firewall began redirecting traffic heading for China and beaming it at GitHub, most likely with the intention of overloading the site. Known as a distributed denial of service, the attack targeted sites hosted by GitHub that linked to sites blocked in China, including that of The New York Times.

It is unclear why the attacks stopped, but analysts said the episode represented a dangerous change in strategy that threatened free speech online. Instead of simply blocking traffic from entering China, the new approach aggressively went after foreign sites deemed objectionable by Beijing.

On Wednesday, President Barack Obama authorized financial sanctions against malicious overseas hackers and companies that knowingly benefit from online espionage. Long in the works, the new policy by Obama was most likely not intended to address attacks like the one on GitHub. Nonetheless, the episode could become a new issue in an already tense relationship between the United States and China over online attacks.

© 2015 New York Times News Service