The following signature were invalid: EXPKEYSIG ED444FF07D8D0BF6 error apt update linux.

The following signature were invalid: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository error apt update and upgrade
Source codes link here http://bugs.mb-techs.com/code
E: The repository ‘http://http.kali.org/kali kali-rolling InRelease’ is not signed.
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.
N: See app-secure

run this command as the root user wget -q -0 – https://archive.kali.org/archive-k ey.asc apt-key add

If you are getting more bugs, share them to this site http://bugs.mb-techs.com/bug/create and will dael with it imadiately. Thanks!