It was quite short about a guy who landed on a planet & somehow got alien paint on himself. The paint grew bigger & when it got to his head he would die. Anyone? Thanks!
This is 'A Can of Paint' by A.E. Van Vogt
Some of the plot (from Wikipedia)..
The protagonist lands on Venus, the first man to successfully make the journey without falling into the Sun.Exiting the ship to begin exploring, he notices a cube-like object with a handle on it just outside the door. He picks it up and it speaks to him through mind telepathy. "I contain paint..." is all he manages to hear before a small amount squirts out onto his shirt and he drops the cube. The paint glows and has all the colors of a rainbow.
He soon notices that the paint is spreading, and when he removes his shirt it jumps onto his skin. When he attempts to rub it off, it flows back on. He then attempts to use various chemicals to remove it, using every solvent he can find and even some of his precious rocket fuel.
None of these work, so he tries a screw-top container which he uses to scoop it off, locking it within so it cannot flow back. After filling part of a bucket, he notices that there is no less paint on him than before – it appears to be self-repairing.
He also notices that he is growing extremely hot, as it is also a powerful insulator. He is bemused by the fact that this paint appears to be perfect; it comes in all colors, applies itself, repairs itself, and insulates as well. Unfortunately that insulation quality will kill him due to overheating, long before the equally worrying possibility of it covering his body completely.