On Tuesday, March 8 the Ozaukee County Sheriff’s Office was advised of a data security breach to the Ozaukee County’s payroll and tax portal software “Greenshades”. The data breach was first learned of after numerous county employees reported having their tax returns filed fraudulently.

The investigation into the possible source of the data breach revealed on Sunday, February 14 numerous logins from suspicious IP addresses were made to approximately 200 employee Greenshades accounts. During these suspicious logins, employee W-2 and 1095C tax forms were viewed. Employee personal identifying information that was potentially obtained included names, addresses, Social Security numbers, along with the names and Social Security numbers of family members who were covered under their insurance.

The investigation so far has determined that the data security breach did not take place internally or locally. The Ozaukee County internal security network has been tested and does not appear to have been breached. It appears the Greenshades software was breached from an out of state source.

The Ozaukee County Sheriff’s Office is working with the Department of the Treasury/Internal Revenue Service (IRS) and the Wisconsin Department of Revenue on this investigation.