muffler shield gone

[Benzomatic126]

I've been posting my mercedes questions for awhile on tech help about my 380 SEL; but this question could be about any car I suppose. (vw jetta)

I have a muffler in the rear of the car that has just "shed" its "outer layer" of metal (thin). Salt rusted it right off.the rest of the muffler looks very solid. Does this present a safety hazzard? I know most people will say "just put on a new muffler", but if it does not need one, I will pass until it falls apart.

Does anyone know their mufflers??

Thanks!