more than likely, your trunk opening is a result of your trunk release on your keyfob. this isn't a civic thing...this has been going on for years with the trunk release on fobs that in pockets.
i know on my previous '11 sonata, people were complaining of the same issue. most realized it was them accidentally pushing the button when they removed the key out of pocket, or something else in the pocket/purse that was opening it. their first rebuttal was why isn't the doors unlocking then? i find it hard to believe that i'm only hitting the trunk button. well, if you unlock your doors with keyfob, they will automatically 're-lock' themselves after a set period (usually 30 seconds). so, you may be unlocking your doors as well, but, they will lock back up...trunks can't do that.
there was a slide switch/lock on the inside of the trunk that would disable the keyfob function. this worked for the majority of them. i personally, have never had the issue, but i also keep very little items in the pocket with my fob.
i am not familiar enough with the 10th gen to see if there is a built in work around/fail safe or not. manual might provide that information.
hiding from those who might be looking for me