A notorious hacker who claims to "fight for the dignity of Muslims" though peaceful means attacked Twitter on Tuesday, publishing private information online from the accounts of thousands of the social-media company's users.

The self-described Mauritania Attacker leaked details to over 15,000 accounts to a public file-sharing service. However, he does not appear to have gotten a hold of users' passwords. In an interview with a cybersecurity website, the 23-year-old hacker claimed to have access to Twitter's entire user database and that "no account is safe from him."

A Twitter rep indicated the company has "investigated the situation and can confirm that no Twitter accounts were compromised."

The Mauritania Attacker has gained notoriety in recent months for leading a collective known as AnonGhost in carrying out a variety of attacks on a range of American, British and Israeli websites. Attacks typically involve either stealing confidential information or defacing websites with anti-Zionist sentiment. In April, AnonGhost even broke into the databases of several Israeli government websites.

While Mauritania Attacker isn't believed to be in possession of passwords, the data he published online revealed he has log-in details including user IDs and "associated OAuth tokens," which control the access of third-party clients to Twitter. Sources indicate a third-party app suspended by Twitter months ago may have been the source of the breach.

Security experts are cautioning Twitter users to change their log-in information to third-party Twitter clients as a protective easure.


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