Oil in plug tubes

[WoodyZ666]

Hi all.

Just back from a road trip and had a misfire. Error code was P0300 random / multiple cylinder misfire. Pulled the coil packs and did resistance check. All were 1.6 except one at 1.48.

Noticed lots of oil in the plug tubes and 5 out of the 6 cylinders. What would cause the oil leak, is it a cam cover gasket issue and would you think that the oil could cause a shorting out and give a misfire. Any advise appreciated before I lose my mind! 

Thanks

Andy