The Russian hackers behind the massive SolarWinds breach have only escalated their efforts to steal tech companies’ private information, according to Microsoft Corp. researchers. This latest campaign, which began in May, has targeted more than 140 companies, with as many as 14 being successfully breached, the experts said. “This recent activity is another indicator that Russia is trying to gain long-term, systematic access to a variety of points in the technology supply chain,” Tom Burt, a corporate vice president for customer security and trust at Microsoft, explained. The SolarWinds breach—in which Russian hackers infiltrated at least a dozen U.S. government agencies—was ultimately blamed on Russia’s foreign intelligence service, prompting President Biden to impose sanctions on Moscow and expel diplomats.