Two Democratic senators on Wednesday asked major vendors of U.S. voting equipment whether they have allowed Russian entities to scrutinize their software, saying the practice could allow Moscow to hack into American elections infrastructure.

The letter from Senators Amy Klobuchar and Jeanne Shaheen followed a series of Reuters reports saying that several major global technology providers have allowed Russian authorities to hunt for vulnerabilities in software deeply embedded across the U.S. government.

The senators requested that the three largest election equipment vendors — Election Systems & Software, Dominion Voting Systems and Hart Intercivic — answer whether they have shared source code, or inner workings, or other sensitive data about their technology with any Russian entity.
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