Yeah, google for "cable luber," it's a useful tool. Tips:

1. wear protective eyewear. Sometimes they backfire.

2. grab the cable luber with a rag, because they can lose quite a bit of lube and make a mess.

3. when lubing a cable on or near a disc brake, take all necessary measures to avoid even the slightest oil contamination of the disc rotor (remove the wheel) and the brake pads (remove them or wrap the entire caliper in a rag or something).


Furthermore, lubing a cable that already has contamination or corrosion may not help much.