Premiere Pro Over-Exposure Recent Change When Exporting

Basic color management.

You have probably an HLG clip, a form of HDR. And you didn't have the bew color management settings correct for your export color space.

Color Workspace Lumetri panel Settings tab. It's all there now.

Make sure auto detect log and auto tonemapping are on. Display Color Management also.

Set your Display gamma to whatever you need, and sequence to whatever you want to work in. Either HLG/HDR or Rec.709/SDR. I recommend the later as HDR is still the Wild Wild West.

Then use an export preset that matches your sequence color space. Rec.709 sequence, do not use any preset with HLG or PQ in the preset name.

If an HLG sequence, use a preset with HLG in the name.