Is a sidewall bubble or bulge dangerous?

A sidewall bubble or bulge is dangerous and you should replace the tire immediately

There’s no way to fix a tire sidewall bubble or tire bulge. It’s dangerous to drive on either and the bubble or bulge can blow out and cause loss of control at any time. You must replace the tire.

Impacts cause belt damage and belt damage causes the bulge

Potholes and curb kisses can severely break the steel belts in your tires, causing the sharp ends to puncture the liner and allow air in the space between the liner and the sidewall. That’s what causes a sidewall bubble. An impact can also cause the belt to separate, causing a sidewall bulge. In either case, the tire is damaged beyond repair and is dangerous to drive on. Remove the tire and put on the spare until you can get the tire replaced

A broken belt punctures the tire liner, allowing air into the sidewall which causes a tire bubble.

Driving on a tire bulge or tire bubble is dangerous

When the steel belt punctures the inner liner, air bleeds between the radial plies and the sidewall, causing a bubble. If you continue to drive in this state, the air will move to other portions of the sidewall, resulting in catastrophic failure.

If you continue to drive on a tire with a punctured liner, you can get multiple tire bubbles. These tires are extremely dangerous to drive on

Here’s what happens when tire bulges pop

No, these tires weren’t slashed. The tire bulges just popped

Did someone slash by tire? Nope. You had a broken belt that leaked air into the sidewall. That causes tire bulges/bubbles that you missed and kept driving on it. Then they popped

This is what happens when you continue to drive on a damaged tire.