Exclusive Big data breaches found at major email services expert FRANKFURT Reuters Hundreds of millions of hacked user names and passwords for email accounts and other websites are being traded in Russias criminal underworld, a security expert told Reuters. The discovery of 2. Mail. ru MAILRq. L, Russias most popular email service, and smaller fractions of Google GOOGL. O, Yahoo YHOO. O and Microsoft MSFT. O email users, said Alex Holden, founder and chief information security officer of Hold Security. RECOMMENDED Oil bankruptcy wave nears size of telecom bust. It is one of the biggest stashes of stolen credentials to be uncovered since cyber attacks hit major U. S. banks and retailers two years ago. How To Report Hacked Gmail Account' title='How To Report Hacked Gmail Account' />Hundreds of millions of hacked user names and passwords for email accounts and other websites are being traded in Russias criminal underworld, a security expert told. Holden was previously instrumental in uncovering some of the worlds biggest known data breaches, affecting tens of millions of users at Adobe Systems ADBE. O, JPMorgan JPM. N and Target TGT. N and exposing them to subsequent cyber crimes. READ MORE Facebook pays 1. Instagram hacker. The latest discovery came after Hold Security researchers found a young Russian hacker bragging in an online forum that he had collected and was ready to give away a far larger number of stolen credentials that ended up totalling 1. After eliminating duplicates, Holden said, the cache contained nearly 5. Mail. ru accounts a big chunk of the 6. Mail. ru said it had at the end of last year. It also included tens of millions of credentials for the worlds three big email providers, Gmail, Microsoft and Yahoo, plus hundreds of thousands of accounts at German and Chinese email providers. This information is potent. It is floating around in the underground and this person has shown hes willing to give the data away to people who are nice to him, said Holden, the former chief security officer at U. S. brokerage R. W. Baird. These credentials can be abused multiple times, he said. LESS THAN 1 Mysteriously, the hacker asked just 5. Hold researchers agreed to post favourable comments about him in hacker forums, Holden said. He said his companys policy is to refuse to pay for stolen data. In the space of one hour, my entire digital life was destroyed. First my Google account was taken over, then deleted. Next my Twitter account was compromised, and. Gmail, Googles free email service, is one of the worlds most popular email programs. A GoogleGmail account extends into a host of other web services. How to Hack Facebook Password Account this trending topics actually going through our contact mail and also the request tutorial form very intensively. The Windows 10 Mail app can do more than just send and receive email from your Microsoft accountit can handle your Gmail as well. Your email account may be worth far more than you imagine. 2 Player Gold Miner Hack here. Gmail Customer Support Helpline UK 448004049736 resolving Google Mail UK problems like Gmail account blocked,forgot Gmail password, Gmail Account hacked etc. Report on noreplyaccounts. Name Google Account Recovery, location, history, and user submitted comments for noreplyaccounts. Cloud. The difference between Gmail, a Google Account, an Apps Account, and an Apps for Business Account. Such large scale data breaches can be used to engineer further break ins or phishing attacks by reaching the universe of contacts tied to each compromised account, multiplying the risks of financial theft or reputational damage across the web. RECOMMENDED Commentary Never. Trump, Maybe. Hillary. Hackers know users cling to favourite passwords, resisting admonitions to change credentials regularly and make them more complex. Its why attackers reuse old passwords found on one account to try to break into other accounts of the same user. Mail. ru logo is seen in front of a displayed binary code in this illustration taken, May 4, 2. REUTERSDado RuvicIllustration After being informed of the potential breach of email credentials, Mail. Reuters We are now checking, whether any combinations of usernamespasswords match users e mails and are still active. As soon as we have enough information we will warn the users who might have been affected, Mail. Mail. rus initial checks found no live combinations of user names and passwords which match existing emails. A Microsoft spokesman said stolen online credentials was an unfortunate reality. Microsoft has security measures in place to detect account compromise and requires additional information to verify the account owner and help them regain sole access. Yahoo and Google did not respond to requests for comment. Yahoo Mail credentials numbered 4. IDs discovered. Meanwhile, 3. Microsoft Hotmail accounts and 9 percent, or nearly 2. Gmail, according to Holden. Thousands of other stolen usernamepassword combinations appear to belong to employees of some of the largest U. S. banking, manufacturing and retail companies, he said. Stolen online account credentials are to blame for 2. Cloud Security Alliance. In 2. 01. 4, Holden, a Ukrainian American who specialises in Eastern European cyber crime threats, uncovered a cache of 1. His firm studies cyber threats playing out in the forums and chatrooms that make up the criminal underground, speaking to hackers in their native languages while developing profiles of individual criminals. Holden said efforts to identify the hacker spreading the current trove of data or the source or sources of the stolen accounts would have exposed the investigative methods of his researchers. Because the hacker vacuumed up data from many sources, researchers have dubbed him The Collector. Ten days ago, Milwaukee based Hold Security began informing organisations affected by the latest data breaches. The companys policy is to return data it recovers at little or no cost to firms found to have been breached. This is stolen data, which is not ours to sell, said Holden. This version of the story has been refiled to make amends to attribution of comments by Mail. Editing by Mark Trevelyan.