There's been a bug with Succession Drakania ever since the Hit Count/DR/Evasion changes were implemented.

All of the skills affected by the passive Prime: Dragonborn Constitution are triggering Forced PvP when used within a world boss PvP disabled area and within range of an ally (ex. guild/party member).

If the Forced PvP happens to linger other players can kill you. Additionally each instance of the Forced PvP activating will consume 3k Karma, like it normally would when Forced PvP is initiated.
I've sent a few tickets previously, but I've been seeing more and more people getting affected by this bug so I decided to post this here as well.

Below is a screenshot of the skill as well as a video showcasing the bug in question:

Hi!

After some testing, I have noticed 2 skills triggering this issue.

First one is 100% Rage Blackspirit Prime: Marktanan's Flourish IV. The other is Prime: Ascent.

So to counter this you just have to not spam your 100% rage skill and not use your 2nd most damaging skill near an ally... Maybe I'll visit Muiquun someday.

Edit: I just found one more thing. Hold to charge Ion from Prime Suindering claw, Prime: Brimbolt and Prime: Eviscerate will trigger this issue, so this could go with 100% Rage Blackspirit Prime: Marktanan's Flourish IV, cause that charges Ions. 

I noticed this, too with my Drakania @ Isabella fights - randomly getting Karma dropped messages but PvP is not shown als enabled. I was wondering, what is happening here.

Can confirm this bug almost got piled on at Bulgasal because i turned red right before it died had to bail out of there as quick as I could in confusion. I have not been able to find the cause like OP here though.

Like I said in my original post, any of the skills listed in the skill Prime: Dragonborn Constitution that use its ally cleansing effect will trigger the world boss automatic Forced PvP. I showcase all the skills affected in the video including what you mentioned, any skills that can be charged for Ions and Markthanan's Scale.

Edit: You do need allies near to trigger the bug. Either guild members or party members.