Here is the first leaked picture of the upcoming Canon RF 50mm f/1.8 STM lens that will be announced together with the Canon RF 70-200mm f/4 L IS USM. There will also be two new lens hoods: ET-83G (WIII) and Lens Hood ES-65B (via Nokishita). The official announcement should be coming in the next 1-2 weeks.
Update - here is the lens design diagram:
