The Equifax Hack Has the Hallmarks of State-Sponsored Pros

In the corridors and break rooms of Equifax Inc.'s giant Atlanta headquarters, employees used to joke that their enormously successful credit reporting company was just one hack away from bankruptcy. They weren't being disparaging, just darkly honest: Founded in the 19th century as a retail credit company, Equifax had over the years morphed into one of the largest repositories of Americans' most sensitive financial data, which the company sliced and diced and sold to banks and hedge funds. In short, the viability of Equifax and the security of its data were one and the same.

Nike Zheng, a Chinese cybersecurity researcher from a bustling industrial center near Shanghai, probably knew little about Equifax or the value of the data pulsing through its servers when he exposed a flaw in popular backend software for web applications called Apache Struts. Information he provided to Apache, which published it along with a fix on March 6, showed how the flaw could be used to steal data from any company using the software.