WikiLeaks appeared to be up and running Wednesday after hackers unleashed a denial-of-service [DoS] attack on the whistleblower Web site Tuesday night.
“WikiLeaks.org is presently under attack,” the whistleblower group said on its Twitter feed.
The denial-of-service attack follows just days after the WikiLeaks published another batch of the U.S. diplomatic cables. The latest release comes from a comprehensive cache of 250,000 State Department cables, which the whistleblower site obtained and began releasing in periodic intervals since last November.
Following the cables' initial publication last year, a hacker calling himself The Jester executed a retaliatory denial-of-service attack that shut down the WikiLeaks site . However, thus far, no one has yet claimed responsibility for Tuesday’s attack.
This week, WikiLeaks made public around 134,000 diplomatic cables, about 170 of which named U.S. diplomats whose identities were protected.
Among those named was a United Nations official in West Africa and a foreign human rights activist working in Cambodia, according to The New York Times.
Also included in the batch of exposed cables was one sourced from Australia, which outs 23 Australians allegedly in contact with the radical Islamist cleric Anwar al Awlaki. The cable, which was issued by the U.S. Embassy in Canberra in January 2010, placed the Australian individuals on a no-fly list.
WikiLeaks, a whistleblower public information forum founded by Australian Julian Assange, claimed that it had exposed information from every country with a U.S. diplomatic presence.
During prior releases, WikiLeaks had practiced diligence in maintaining the privacy of individuals mentioned by name in the U.S. cables. The whistleblower site denied that it had deliberately unredacted the information before publishing.
According to Chester Wisniewski, Sophos senior security advisor, the WikiLeaks site suffered a data breach when Assange shared a passphrase with an external source required to decrypt a batch of cables taken by former colleague Daniel Domscheit-Berg.
Domscheit-Berg returned the cables last November, after which WikiLeaks supporters subsequently made the contents available in a public archive. However, WikiLeaks supporters failed to notice that the archive contained a hidden directory with the encrypted file holding the cables, and unintentionally made the file public, according to Wisniewski.
The external source to whom Assange had given the encryption key then publicly disclosed it this spring.
“The result? The uncensored cables are now publicly downloadable and could blow the cover of American informants around the world,” Wisniewski said in a blog post.
Consequently, many feared that the unredacted information contained in the latest release could compromise national security by exposing the names of U.S. informants all over the world, while putting U.S. diplomats in harm’s way, according to The New York Times.