On Monday, Team Inj3ct0r (1337day) claimed to hack Apache Tomcat Version 5.5.9 of the North Atlantic Treaty Organization (NATO), reported the Hacker News. 

A backup of random 2,646 files were leaked from NATO's server, uploaded by the hacker group as an online archive.

Team Inj3ct0r told the Hacker News that the reason of hacking is nuclear weapons, its development and financing.

Since its formation in 1949, NATO bases its objectives on the North Atlantic Treaty of 1949, which requires each member state to share the risk and responsibility of upholding international peace and security, according to Nuclearfiles.org. Nuclear weapons have formed part of its collective defense policy, which calls for insuring the ability to carry out strategic bombing including the prompt delivery of the atomic bomb. This is primarily a US responsibility assisted as practicable by other nations. NATO upholds a policy of nuclear deterrence, or nuclear sharing, which involves basing nuclear weapons on the territories of non-nuclear weapon states.

The hackers claimed their ability to deface NATO's website, but they would not carry it out. Taking the backup of server data, the hacker group has attempted to distribute it on the Internet. 

NATO, the world's most powerful military alliance, has been threatened by the hacker group Anonymous last month.