Yesterday morning, a DDoS attack temporarily disrupted traffic to Wikileaks hours ahead of the “Cablegate” release of leaked US documents. Wikileaks announced the outage on a Facebook update and Twitter post around 11:00am EST while simultaneously derogating the attack and insisting “El Pais, Le Monde, Speigel, Guardian & NYT will publish many US embassy cables tonight, even if WikiLeaks goes down”.
In the below graph, I show traffic to one of Wikileak’s primary hosting provider on November 28 through 100 ATLAS providers around the world. At approximately 10:05am EST, traffic abruptly jumps by 2-4 Gbps as the attack begins.
Shortly after the attack started, Wikileaks redirected DNS from its AS8473 Swedish hosting provider to use mirror sites hosted by a large cloud provider in Ireland (and later the US as well). While the DDOS attack generated an outpouring of blog posts, news articles and tweets, it appears to have had little impact on the Wikileaks “Cablegate” disbursement of documents.
Overall, at 2-4 Gbps the Wikileaks DDoS attack was modest in the relative scheme of recent attacks against large web sites. Though, TCP and application level attacks generally require far lower bps and pps rates to be effective (more discussion of recent DDoS trends is available here). Engineering mailing list discussion also suggests the hosting provider and upstreams decided to blackhole all Wikileaks traffic rather than transit the DDoS.
At the time of this writing, all Wikileaks domains are reachable from servers in the US, Europe and Asia. The New York Times and most other major media outlets also have since published extensive synopses of the leaked documents.
While the source of the attack is unknown, blogs and social networking sites have alternatively blamed governments and vigilante hacker groups. At least one twitter account with a history of past attacks (“the Jester”) has claimed responsibility. In earlier tweets, the Jester boasted of using low bandwidth application layer attacks instead of relying on large botnets (all of which is consistent with the data ATLAS observed for this Wikileaks attack).
Wikileaks also came under fire in 2008 with a 500 Mpbs DDoS attack shortly before the release of leaked Swiss bank documents.
Update: A follow-on blog post analyzing the second day of Wikileaks DDoS attacks is now available here.