According to Help Net Security, the Twitter web site appeared to be defaced by someone called "Iranian Cyber Army". The situation was fixed and as it turned out, hack was a result of DNS hijacking.
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Initial message from the official Twitter account:
Initial message from the official Twitter account:
Twitter's blog post that followed:Twitter's DNS records were temporarily compromised but have now been fixed. We will update with more information soon.
As we tweeted a bit ago, Twitter's DNS records were temporarily compromised tonight but have now been fixed. As some noticed, Twitter.com was redirected for a while but API and platform applications were working. We will update with more information and details once we've investigated more fully.