Light leak
Light leak
It looks like your shutter is hanging up at the bottom of the exposure (top of the picture because they are reversed when taken.) The light strike is not exactly parallel to the bottom, suggesting that at least sometimes when the shutter fires it hangs up on one side (load side.) Try looking at the back of the shutter without film in the camera and shot it multiple times at each shutter speed. If the shutter is not coming down evenly or it hesitates at the bottom (probably cannot see this as light strike is not too over exposed) it may have dirt in the track.
As a,first fix try setting the shutter to time and fire it. While the shutter is open blow out and gently clean the shutter track. There may be film chips or other small debris there. If this fails, you will probably need CLA/shutter job.
Bill