If it's just light surface rust the stand should be safe to operate , any pitting would be suspect though . Give the rusty areas a light coat of mineral oil and then inspect them again . All cables have built in corrosion protection via the lubricant inside inside them , and a pin would have to be very corroded to no longer bear it's rated weight . Pay particular attention to the arms where the pins connect , if you see pitting around the holes don't use the stand . Inspect the holes around ALL of the fasteners , be sure to check for loose or corroded fasteners . Wear is more likely to be a problem than rust .