Vinegar is the pro move for cast iron rust

Yes, you can save it. Vinegar works better than baking soda.

Rust is just iron oxide, and vinegar (acetic acid) dissolves it chemically. Baking soda is mildly abrasive but not acidic enough to break down rust efficiently—it’s better for scrubbing off food residue or neutralizing odors.

Here’s the quick fix: scrub off any loose rust with steel wool or a chainmail scrubber. Then do a 50/50 soak of white vinegar and water—30 minutes for light rust, up to an hour for heavy spots. Check periodically. Pull it out, scrub again, rinse thoroughly with water, and dry immediately (like, put it on the stove on low heat to evaporate every drop). Then rub a thin layer of cooking oil all over, inside and out, and give it a short oven bake at 350°F for an hour to re-season.

Don’t let it soak in vinegar overnight—that will etch the iron and ruin the seasoning. If the rust is deep pitting, you might need a second