I would say BS. Did they send it from a company email or a gmail or you own spoofed email? Did they send a link from their company? If they found you on career builder, then they have your information. It was on your resume.

I got an email from someone about a secret shopper job. I had in fact applied for one last year or so, but the "from" address was my own and they provided no company name. Just told me I could make $5k a month and asked for all of my information. I wrote back to tell them I was interested but didn't feel comfortable sending my info over email especially since it had not come from a company email or any type of email at all. I asked if they had a website I could check out. They never responded, but I got several of the same emails from different signature names over the next few weeks.