Reuters reports that a Russian hacker was able to gain access to hundreds of millions of accounts on the most popular e-mail servers, putting users’ names and passwords at risk, and is now selling the stolen information online.

About 272.3 million accounts were compromised, including 24 million Gmail accounts, 40 million Yahoo! accounts, and 33 million Microsoft Hotmail accounts. The largest portion of the data theft — 53 million accounts — was from users of Mail.ru, Russia’s most popular e-mail service.

Reuters reports the security breach represents one of the “biggest stashes of stolen credentials” since hackers attacked U.S. banks and retailers two years ago.

“This information is potent,” says Alex Holden, founder and chief information security officer of Hold Security, the firm that announced the security breach. “It is floating around in the underground. … These credentials can be abused multiple times.”

Source: “Exclusive: Big Data Breaches Found at Major E-mail Services,” Reuters (May 5, 2016)

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