The Linux kernel through 5.8.13 does not properly enforce the Secure Boot Forbidden Signature Database (aka dbx) protection mechanism. This affects certs/blacklist.c and certs/system_keyring.c.
Exploitability
AC:LAV:LPR:HUI:RScope
S:UImpact
A:HC:HI:H6.5/CVSS:3.1/AC:L/AV:L/A:H/C:H/I:H/PR:H/S:U/UI:R