Leaking at Antenna Base

2012 DCSB stock w/no mods. I just noticed that there is a sticky type leak at the antenna base. Could this be some type of sealant/caulk that was used to seat it?

 

I have never seen anything around an antenna base.... Post a pic and share.

 

Thanks. Here's a shot of it but it doesn't really show up well with the light I had. Coming from under the rubber housing that covers the connection. Cloudy looking stain that won't come off with normal cleaner. Gonna try a bit of polishing compound very lightly and see if that gets it. Pulled antenna mast and I can't really see any corrosion where it seats. Didn't want to pull the rubber base off since I don't know what type of seal attaches it to the truck.