Wasn't that one of the main MOP's for Russian infantry to attack German tanks in WW2? Run up to it, stick a grenade in a weak spot, run away as fast as you could? I assume modern tanks would be quite different from WW2 tanks, but still - someone has done it before.
My grandad drove a wrecker in a tank destroyer group in WWII, deployed to Europe. He didn't talk much about it until his mind was on the way out, but said one of the more effective techniques to disable tanks was dumping gas on the engine intake.
Soviets did improvise a lot of anti-tank weaponry, but that's because they didn't have anything decent in service for pretty much the entirety of the war. Their standard-issue anti-tank rifles were so underpowered, the crews were instructed to shoot at the observation slits, and if those weren't accessible, then at the antenna (to at least disable the radio).
These days, infantry taking on a tank would just use an RPG or an ATGM.
