I'm cleaning this cabinet above the range/micro and noticed this mark on the back. I mostly keep cooking oils, vinegars, etc in here. Does this look serious?
Update: well it ain't pretty, but it shouldn't burn the house down. For anyone concerned, my electrician approves. Thank you all for your help today.
Looks to me like something is scorching the wall. Could have been something inside the cabinet, like putting away a cast iron pan while it's still hot, but my guess is you have a screw in the wall there that is screwed into a shorted electrical cable.
I could definitely be wrong, but I'd cut a hole and see what's back there anyway.
I agree about cutting away the drywall. Easy to fix after, especially since inside a cupboard. I would avoid touching with metal and wear insulated gloves I think.