Exotic quest Hunger Pangs leads to Promethean code (heroic)

Hey all,

EDIT: Picture of the quest

I got an exotic quest from Eris, labelled "Hunger Pangs: Promethean code (heroic)". I have no idea what it leads to, or how I triggered it. It appeared as a notification above the tower, after I had just come back from a dreadnaught patrol with my fireteam.

Here's a link to a destiny tracker datamined listing, however it only lists the reward as 'classified'.

Hunger Pangs Entry.

Will update with a picture shortly, and will update as I try to progress the quest.