I don't know, maybe someone has reported this already, because the map is quite old. Anyways, there are a few spots on "150th Box" flag, where you can clip through the terrain. To do so, you need to jump out of the trench, crouch while in mid-air and go prone afterwards. I've found 2 spots where you can do this (maybe there's more):




I also made a video: https://youtu.be/axQBOhocLs0

So yeah, you can shoot people and/or cap the flag from there and no one can even see you. Hope you guys can fix it and sorry for my English I hope you understand