Thousands of North Korean techies have devised schemes to infiltrate foreign companies, including some in the US. China and Russia are also prone to hiring these agents, meaning that this problem transcends geography and geopolitics. There are steps US companies can take to avoid hiring North Korean plants, and they almost certainly will become more aware of this problem and address it. This relatively low-level operation can be solved rather easily by US companies.
American companies have been getting duped by savvy North Korean tech workers, allowing North Korean nationals to funnel money back to their home country. US-based companies either ignored warnings to remain diligent, or they simply didn't care enough to protect against foreign plants within their ranks. Either way, North Korea seems to be ahead of US internet security norms and processes. US companies also need to bear the brunt of better vetting and security protocols.