TIL that during the Gulf War, American made color copiers that copied Iraq's war plans were transmitting their locations to US forces for more accurate bombing.

https://en.wikipedia.org/wiki/Gulf_War#United_Kingdom:~:text=American%2Dmade%20color%20photocopiers%20were%20used%20to%20produce%20some%20of%20Iraq%27s%20battle%20plans.%20Some%20of%20the%20copiers%20contained%20concealed%20high%2D…

https://www.reddit.com/r/todayilearned/comments/1537j97/til_that_during_the_gulf_war_american_made_color/