of which use password design vulnerabilities (as found in the Microsoft LANManager system) to increase efficiency. These programs are sometimes used by system administrators to detect weak passwords proposed by users. Studies of production computer systems have consistently shown that a large fraction of all user-chosen passwords are readily guessed automatically. For example, Columbia University found 22% of user passwords could be recovered with little effort. According to Bruce Schneier, examining data from a 2006 phishing attack, 55% of MySpace passwords would be crackable in 8 hours using a commercially available Password Recovery Toolkit capable of testing 200,000 passwords per second in 2006. He also reported that the single most common password was password1, confirming yet again the general lack of informed care in choosing passwords among users. (He nevertheless maintained, based on these data, that the general quality of passwords has improved over the years—for example, average length was up to eight characters from under seven in previous surveys, and less than 4% were dictionary words.) Incidents On July 16, 1998, CERT reported an incident where an attacker had found 186,126 encrypted passwords. At the time the attacker was discovered, 47,642 passwords had already been cracked. In September 2001, after the deaths of 658 of their 960 New York employees in the September 11 attacks, financial services firm Cantor Fitzgerald through Microsoft broke the passwords of deceased employees to gain access to files needed for servicing client accounts. Technicians used brute-force attacks, and interviewers contacted families to gather personalized information that might reduce the search time for weaker passwords. In December 2009, a major password breach of the Rockyou.com website occurred that led to the release of 32 million passwords. The hacker then leaked the full list of the 32 million passwords (with no other identifiable information) to the Internet. Passwords were stored in cleartext in the database and were extracted through a SQL injection vulnerability. The Imperva Application Defense Center (ADC) did an analysis on the strength of the passwords. In June 2011, NATO (North Atlantic Treaty Organization) experienced a security breach that led to the public release of first and last names, usernames, and passwords for more than 11,000 registered users of their e-bookshop. The data was leaked as part of Operation AntiSec, a movement that includes Anonymous, LulzSec, as well as other hacking groups and individuals. The aim of AntiSec is to expose personal, sensitive, and