The IRS revealed on Tuesday that it discovered and stopped an automated cyberattack on its e-filing personal identification number (PIN) system last month. According to the IRS, the cybercriminals used information stolen “elsewhere outside the IRS” to generate e-file PINs for stolen Social Security numbers (SSNs). E-file PINs are used by some taxpayers to electronically file their tax returns.
Although no personal taxpayer data were compromised or disclosed by the breach, the IRS noted that the cybercriminals succeeded in using 101,000 SSNs to access e-file PINs (out of 464,000 attempts).
http://www.journalofaccountancy.com/news/2016/feb/irs-data-breach-expose...