A scuffed tire sidewall could be nothing to worry about, or it could be a sign of the beginning of sidewall damage. The only way to tell is to physically inspect the tire.
Check Sidewall For Damage
Take a wet towel and remove the scuff mark, then dry the area with a dry towel. Run your finger over the tire to try to determine if any damage has been done.
If it feels mostly smooth, that's good news—you're unlikely to be looking at significant risk.
If it feels like sandpaper, then you have the beginnings of sidewall damage. A sidewall scuff can eventually turn into a sidewall tear, and that can cause you to lose control of your vehicle. So if you determine you have sidewall scuff damage, you should get your tire replaced immediately.