@chenoodles It's not illegal. But we have to ask what happens if they lost it and didn't bother to tell you, and by the time you find out someone's already maxxed the limit. And you'll be liable for that.
Banks don't care. You sendiri wreck your own credit score saja. One credit card maxxed to the limit is nothing more than a to be paid debt on their books. You on the other hand....
I strongly suggest a supplementary card, with the monthly limit set to a reasonable number. Don't give a rm10k limit card for petrol for motorcycle.