Operation Anti-Security, also referred to as Operation AntiSec or #AntiSec, is a series of hacking attacks performed by members of the hacking group LulzSec and Anonymous, and others inspired by the announcement of the operation. LulzSec performed the earliest attacks of the operation, with the first against the Serious Organised Crime Agency on 20 June 2011. Soon after, the group released information taken from the servers of the Arizona Department of Public Safety; Anonymous would later release information from the same agency two more times. An offshoot of the group calling themselves LulzSecBrazil launched attacks on numerous websites belonging to the Government of Brazil and the energy company Petrobras. LulzSec claimed to retire as a group, but on 18 July, they reconvened to hack into the websites of British newspapers The Sun and The Times, posting a fake news story of the death of the publication's owner Rupert Murdoch.
Anonymous released their first cache of the operation on 27 June 2011, taken from an anti-cyberterrorism program run by the United States Department of Homeland Security and Federal Emergency Management Agency. They continued attacks on the Arizona government. They also launched attacks against the governments of Brazil, Zimbabwe, and Tunisia. Their most recent attacks have been against large corporations, NATO, and various United States law enforcement websites. Anonymous has used the stolen credit card numbers of police officers to make unauthorized donations to various causes. Others have also committed hacks in the name of the operation, including a hack into the Fox News Twitter account to post a false news story about the assassination of President of the United States Barack Obama and attacks on the websites of government entities in various countries. The groups involved have published sensitive government and corporate information, as well as the email addresses, names, and social security numbers, and credit card numbers of website users.
Law enforcement has launched investigations into many of the attacks committed as part of Operation AntiSec. At least seven arrests have been made in connection to activities related to the operation, including the arrests of two purported LulzSec members, a man who provided LulzSec with security vulnerability information, and four alleged members of AntiSec NL, a group inspired by the operation.