https://www.theverge.com/2018/7/17/17582818/election-software-maker-remote-access-voting-machine

A major voting machine maker, Election Systems & Software, revealed in a letter to a US senator that it installed remote-access software on its machines over a period of six years. The revelation raises substantial security concerns, as reported by Motherboard, which obtained the letter.

ES&S admitted in the letter sent to Senator Ron Wyden (D-OR) in April that it had provided the embattled remote connection software called pcAnywhere to “a small number of customers between 2000 and 2006.” In those years, ES&S was one of the top voting machine makers in the United States. The company makes systems used to manage voting booths and to tabulate the final results from those booths. In 2006, at least 60 percent of ballots cast in the US were added up by ES&S systems.