Kali Linux: Fix "Missing Key" Error on apt update

20 May 2025

Error on apt update:

Missing key 827C8569F2518CC677FECA1AED65462EC8D5E4C5, which is needed to verify signature.

Kali rotated its repository signing key. Download the new keyring and update:

sudo wget https://archive.kali.org/archive-keyring.gpg -O /usr/share/keyrings/kali-archive-keyring.gpg
sudo apt update

More info.