You might notice something is amiss when you set up a new Kali Linux VM from the Azure VM Marketplace…

anthturner@mykalibox:~$ sudo apt update
Get:1 http://kali.download/kali kali-rolling InRelease [30.6 kB]
Err:1 http://kali.download/kali kali-rolling InRelease The following signatures were invalid: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository <devel@kali.org>

This is happening because between the release of the Kali Rolling image used on the VM, and the current date, one or more certificates have expired. Right now, this happens with the usage of the current Kali Linux image present in the Azure VM Marketplace.

Fortunately a quick fix can get you back up and running!

anthturner@mykalibox:~$ wget https://http.kali.org/pool/main/k/kali-archive-keyring/kali-archive-keyring_2020.2_all.deb --no-check-certificate && sudo dpkg -i kali-archive-keyring_2020.2_all.deb

This will pull the 2020.2 keyring and install that dpkg to your system. This forces your keyring to move up to date, which will then allow the use of apt commands (or anything else reliant on that!)

Happy Cybersecurity Awareness Month!