I'd be more concerned about listening devices especially key committee Members and staff e.g. foreign relations LAs
I don't have firsthand knowledge of the non-classified working computers of Congress but maybe someone can confirm if IT used SolarWinds and their network is already compromised.
* also individual Member offices are treated basically like businesses in a lot of ways. e.g. the Member can contract/share hire their own IT helpers too. i can't find a source quickly but a few years ago remember the article about some guy working for a few Dems being a dumb ass
* * I'll also add that almost any US citizen can get a meeting inside a Member's office. A house member directly or with a staffer. I'm sure there are a ton of listening devices that metal detectors wouldn't find and that are quick to place surreptitiously