From February to May, data thieves were able to gain access to the tax return information for roughly 100,000 taxpayers, IRS Commissioner John Koskinen said Tuesday.
During those four months, the thieves attempted to get information 200,000 times through the agency's "Get Transcript" online application, Reuters reports, and were successful about half of the time. It wasn't a hack, since the cyber criminals already had names, addresses, Social Security numbers, and other personal information that they used to access the system. IRS data outside of the application was not affected, and the agency said it plans to strengthen its security measures.
Koskinen did not share any information on who might have been behind the attack, and said the data theft was intended to steal information in order to submit fraudulent tax returns next year. "We're confident these are not amateurs," he said. "These are actually organized crime syndicates that not only we but everyone in the financial industry are dealing with."