In a statement issued on Thursday US time, the White House said American intelligence agencies had "high confidence" in this assessment.
To date, no cyber security company, including FireEye, the firm that first made the SolarWinds compromise public, has attributed the attack to any country.
The companies are:
- ERA Technopolis;
- Pasit, AO (Pasit);
- Federal State Autonomous Scientific Establishment Scientific Research Institute Specialised Security Computing Devices and Automation (SVA);
- Neobit, OOO (Neobit);
- Advanced System Technology, AO (AST); and
- Pozitiv Teknolodzhiz, AO (Positive Technologies.
The following description of what the companies do was provided:
"ERA Technopolis is a research centre and technology park funded and operated by the Russian Ministry of Defence. It houses and supports units of Russia’s Main Intelligence Directorate responsible for offensive cyber and information operations and leverages the personnel and expertise of the Russian technology sector to develop military and dual-use technologies.
"Pasit is a Russia-based IT company that conducted research and development in support of Russia’s Foreign Intelligence Service’s malicious cyber operations.
"SVA is a Russian state-owned research institute specialising in advanced systems for information security located in Russia. SVA conducted research and development in support of the SVR’s malicious cyber operations.
"Neobit is a Saint Petersburg, Russia-based IT security firm whose clients include the Russian Ministry of Defence, SVR, and Russia’s Federal Security Service. Neobit conducted research and development in support of the cyber operations conducted by the FSB, GRU, and SVR.
"AST is a Russian IT security firm whose clients include the Russian Ministry of Defence, SVR, and FSB. AST provided technical support to cyber operations conducted by the FSB, GRU, and SVR.
"Positive Technologies is a Russian IT security firm that supports Russian Government clients, including the FSB. Positive Technologies provides computer network security solutions to Russian businesses, foreign governments, and international companies and hosts large-scale conventions that are used as recruiting events for the FSB and GRU."
The UK later said it backed the US announcement. Foreign Secretary Dominic Raab said: "We see what Russia is doing to undermine our democracies. The UK and US are calling out Russia’s malicious behaviour, to enable our international partners and businesses at home to better defend and prepare themselves against this kind of action.
"The UK will continue to work with allies to call out Russia’s malign behaviour where we see it."