Following the November 4th attack, Anonymous once again hacked into the Organization for Security and Cooperation in Europe (OSCE).  Today they have leaked another 55mb of internal documents from OSCE Vienna, dating upto November 11th.

Again, many of the documents are marked as restricted; They have published a 147k PDF file that talk about "Efforts in the field of arms control agreements and confidence– and security–building measures".

The full archive has been uploaded to Par-AnoIA.net "http://par-anoia.net/assessment/at/reprise.zip"

In previous attack, they have leaked files that contain highly sensitive information including bank account numbers, and other monetary transaction details. 

The attack vector was not revealed although it may have been SQLi or perhaps a social engineering attack where an employee was tricked into opening malicious .pdf attachment.