An unhinged maniac shoved and pummeled an 85-year-old man in an unprovoked attack inside a Brooklyn subway station Tuesday, cops said.
The octogenarian was waiting for a Manhattan-bound J train at Broadway Junction around 11:15 a.m. when a complete stranger – later identified as Jeffrey Joseph, 39 – randomly pushed him to the ground, authorities and sources said.
Joseph punched and kicked the senior before taking off, the sources said…