How does input voltage ripple affect output voltage of linear regulator?
You need to be extremely careful when probing noise and ripple as the unwanted signal may be on the ground because of where you are probing, not on the supply rail itself.
It is preferable to use the probe in the x1 setting not x10. And select a ground point very close to the supply you are measuring. The spring ground attachment you probably got with your probe is one way of helping that.
Is it causing a problem? If not it may not be real.
The scope trace shows about 200mV p-p ripple. That shouldn't affect the digital circuitry.