The official and legal method to get these keys is to "dump" them from your own physical Wii U console using homebrew software.
# Common key (Wii U common key) d7b004ab6f7f1a6b5e0a7c9f3e2d8c1a = commonkey cemu keys
The keys.txt file uses a simple key-value format. Example: The official and legal method to get these
Specific codes unique to each individual game, update, or DLC package. For example, The Legend of Zelda: Breath of the Wild has its own specific title key that must be present for the emulator to run it in encrypted formats. Why Does Cemu Need Them? or DLC package. For example
The emulator manages these credentials through a simple plain-text configuration file titled keys.txt , typically located in the root directory of the Cemu installation.