Garlic Infused Oil—Safety
We had a very similar question about making your own garlic oil here:

Botulism, Garlic, Cold pressed Olive oil and mason jars

Oil is effectively an anaerobic environment, which promotes the growth of the bacteria and spores responsible for botulism.

However, these types of risks are common in home canning.  Major factories producing canned or bottled goods are going to want to protect themselves against millions of lawsuits, so they are going to take steps to pasteurize (for lack of a better word) the foods before packaging them.  Commercially-packaged infused oils have probably either been heated, acidified, or filtered to guarantee food safety.

On the other hand, the linked question above demonstrates that there are people out there who aren't taking the appropriate precautionary measures.  If this oil came from a well-known company with a good track record then I would not worry (and you can always contact them if you are worried); however, if it came from somebody you've never heard of, and can't find any reliable information on - i.e. somebody who's making this stuff from home - then I might be a little more concerned.

If you trust the source, then trust the oil.  Otherwise, you might want to try sterilizing it yourself; you need to either heat it to 250° F (121° C) or expose it to acid conditions.  Neither of those things are really desirable; heating it can taint the flavour or even burn the oil depending on what kind of oil it is, and if you want to take the acid route, you basically need to to pickle it.  But there you have it, that's what you can do if you don't trust the safety.