Hackers stole information on 100,000 taxpayers from the online computers of the US Internal Revenue Service, the federal tax agency said Tuesday.
The IRS said the unidentified cyber thieves used information on the specific taxpayers from sources outside the agency to access the accounts, which included crucial identifying information such as birth dates, addresses and social security numbers.
These third parties gained sufficient information from an outside source before trying to access the IRS site, which allowed them to clear a multi-step authentication process, including several personal verification questions that typically are only known by the taxpayer
The IRS said the theft involved its online “Get Transcript” system, which allows users to view all their transactions and reports with the agency.
The hackers tried to access about 200,000 accounts between February and mid-May, and were successful in about half those attempts.