<https://www.theguardian.com/technology/2021/feb/23/solarwinds-hack-senate-he...> Tech executives revealed that a historic cybersecurity breach that affected about 100 US companies and nine federal agencies was larger and more sophisticated than previously known. The revelations came during a hearing of the US Senate’s select committee on intelligence on Tuesday on last year’s hack of SolarWinds, a Texas-based software company. Using SolarWinds and Microsoft programs, hackers believed to be working for Russia were able to infiltrate the companies and government agencies. Servers run by Amazon were also used in the cyber-attack, but that company declined to send representatives to the hearing. Representatives from the impacted firms, including SolarWinds, Microsoft, and the cybersecurity firms FireEye Inc and CrowdStrike Holdings, told senators that the true scope of the intrusions is still unknown, because most victims are not legally required to disclose attacks unless they involve sensitive information about individuals. But they described an operation of stunning size. DoJ confirms email accounts breached by SolarWinds hackers Read more Brad Smith, the Microsoft president, said its researchers believed “at least 1,000 very skilled, very capable engineers” worked on the SolarWinds hack. “This is the largest and most sophisticated sort of operation that we have seen,” Smith told senators. Smith said the hacking operation’s success was due to its ability to penetrate systems through routine processes. SolarWinds functions as a network monitoring software, working deep in the infrastructure of information technology systems to identify and patch problems, and provides an essential service for companies around the world. “The world relies on the patching and updating of software for everything,” Smith said. “To disrupt or tamper with that kind of software is to in effect tamper with the digital equivalent of our Public Health Service. It puts the entire world at greater risk.” [...]