Looks like there is brake fuild leaking from where the master bolts to the booster is there a gasket in there? You can see were it's wet running down the front of the booster.

 

Yes, there is a rubber cup seal. Although that is to keep the vacuum in the booster. Most likely the M/C is bad.

RBob.

 

^what he said, the master is bad. I had a ls1 master go and that exactly what it did, it started weeping around the bolts to the booster.

im sure there is a o-ring inside the master thats causing this, but IDK if its a serviceable part. New masters are cheap, and simpler than tinkering with the 20+ year old one