According to Brian Krebs the compromise of Target’s POS system probably originated with a phishing attack against one of Target’s vendors. This attack compromised credentials of the HVAC vendor and possibly allowed the hackers entrance into Target’s systems.
Interestingly, Brian mentions Ariba, a company I’ve been forced to deal by a large customer of ours. I’m not sure if there really is an attack vector where a vendor can get access through Ariba to the internal systems of the customers. However, my experience with Ariba has been frustrating and problematic, so I’ll be happy to believe their security is as broken as their email.
Email is a great way to interact with people and companies. It’s great for growing communities and businesses. But it is also a way for attackers to get access to your computer and the websites you interact with. Protect yourself, and your company, by running security software. And, please, don’t open attachments or click on links in emails and provide usernames and passwords.

compromise • phishing • security • target