Intuit Lacerte 2017 for Windows in a client/server environment transfers the entire customer list in cleartext over SMB, which allows attackers to (1) obtain sensitive information by sniffing the network or (2) conduct man-in-the-middle (MITM) attacks via unspecified vectors. The customer list contains each customer's full name, social security number (SSN), address, job title, phone number, Email address, spouse's phone/Email address, and other sensitive information. After the client software authenticates to the server database, the server sends the customer list. There is no need for further exploitation as all sensitive data is exposed. This vulnerability was validated on Intuit Lacerte 2017, however older versions of Lacerte may be vulnerable.