This is a legit problem. They pose as American citizens or permanent residents. Sometimes even using a VPN into the US. HR folks would not catch on.
I’ve actually interviewed two of these people over the years. They somehow got through the initial screenings. It’s a bizarre experience. Most of the time there is a significant delay with silence between your question and their answer. It’s as if they’re being fed the perfect answer. Problem is they could never answer or pretended to not understand any follow-up questions.
You could always hear others in the background. One time I was given an answer that I had heard someone else in the room give just 2 minutes before.
The question that really solidified my hunch was about their location. The applicants would always claim to be from a very small town somewhere in the US. In my two experiences I happened to know a lot about those towns. The first said they “really enjoyed the mountains” when I asked what brought them to a Houston suburb. When I asked the other applicant if they had any damage from the hurricane that went through St. Augustine, FL, they replied “What hurricane?”
Now, neither of these people would have been hired even if they had stellar interviews as we do make use of background checks and verification services. This scheme really only works for third-party dev shops or desperate small companies.
I’m glad this problem is getting more attention.