The read is over on Bleeping Computer here:
https://www.bleepingcomputer.com/news/security/lenovo-fixes-flaws-that-can-be-used-to-disable-uefi-secure-boot/
Affected devices are ThinkBook, IdeaPad, and Yoga laptop models. Vendor listing by Lenovo is here:
https://support.lenovo.com/us/en/product_security/LEN-94952
SA