So today I looked under the sink of a house I'm renovating. I noticed a glob of plumbers putty where the drain extension comes out from the wall. I removed the sink and when I did I noticed at some point in time someone jammed a pipe into the drain in the wall. Basically a slip joint and for the sill they used plumbing putty. It looked like it has leaked multiple times. upon further inspection it looks like the drain extension broke off at some point and the old drain appears to be soldered. I'm at a loss where I should go from here. I'm including a picture to help illustrate the problem.
P.S. I also removed a bit of drywall so you can see better.
If that was an old drian(1 1/2 or 1 1/4) it is porbably not soldered, threaded into an iron elbow or tee. It will just seem that way since it has been there for a LONG time. It will be very difficult to remove and cap, assuming that is your goal. An inside pipe wrench might work????