Hi, this has happened to me a few times recently.
I’ll be participating in a big event with a lot of mixed-faction players, like a Grand Hunt, and someone from the opposite faction is PVP-flagged. I’m very careful not to attack them, but while attacking the mobs around them I eventually become PVP-tagged myself.
I assumed that this - AOE attacks hitting a PVP-flagged player and causing me to become PVP-flagged - was an intentional feature, but after some googling it sounds like it shouldn’t be.
I had a look through my combat logs and identified the attack that hit the other player, and it was definitely an AOE effect.
So - is this working as intended?