[1] - https://www.cvedetails.com/cve/CVE-2013-3175/
[2] - https://www.cvedetails.com/cve/CVE-2012-1852/
[3] - https://www.cvedetails.com/cve/CVE-2012-0173/
[4] - https://www.cvedetails.com/cve/CVE-2012-0002/
(Those were just the ones I quickly found that allow RCE on XP SP2 (the oldest thing that they still provided patches for, so most likely to be shared code with Win2k) without requiring active interaction on the target's behalf, e.g. not including "convince target to open X malformed file, receive payload")
It's starting to bother me that the PA election officials keep saying that the voting machines aren't connected networked together, and that one would need 4,500 cards to compromise an election. It's just flatly false, since every county feeds into a central system such as Unity or GEMS, which themselves are provably insecure, and can be infected via the compact flash cards when they're collected. You would only need a few people in key counties to swing an entire election.
What I would give for the days of hanging chads...