If you've never been sexually active (at all), it is possible to contract syphilis? can one get syphilis canker/cold sores inside the lip from kissing

Yes and yes: Although it is rare with present prenatal screening you can inherit syphilis at birth. It is possible but extremely unlikely that you could get it through kissing, (the donor would have to be at just the right phase with germ in the blood and really bad gum disease).Most mouth sores are rather benign and self heal. These are reasonable questions, but exceedingly unlikely to happen.