Automobile manufacturer Toyota recently announced a data breach that may have exposed the emails of up to 300,000 customers for nearly five years. Toyota says the breach resulted from a subcontractor posting source code for Toyota’s “T-Connect” app on the software development platform GitHub in December 2017. This code included an access key to the data server that hosted the email addresses and customer management numbers of T-Connect users. The publicly available source code was found on September 15th, 2022, when Toyota changed the access key. We will explain why the lapse in remediating vulnerabilities can lead to many risks, which may later disrupt corporate operations.