Leaky Master Cylinder

Hey Guys:
I have a 2002 Toyota Tacoma SR5 V-6, ext. cab, I'm finding a few drops of brake fluid were I park my truck, and have to put brake fluid in master maybe every two, two and half weeks. I checked all the lines they seem tight and OK, tightened bolts which hold master cylinder, but I can see were it is running down between master and vacuum tank which master bolts to, its not real wet but just damp and you can see thats were fluid is leaking. Is there a gasket between there that might not be sealing from someone replacing master? I just picked truck up in Jan. so i don't know what has been replaced on the truck. The master does look new. Should I try to pull master off and check it out, will I have to bleed the sysytem if I can get it off without taking lines off? Thanks for your help.
mrbowl300

 

check under the plastic cup, it could be leaking there and just running back to the brake booster connection or it could be leaking from the inside through the back seal where the arm attaches to it