EXPKEYSIG debian ubuntu

Fix EXPKEYSIG 78BD65473CB3BD13

Google Chrome <linux-packages-keymaster@google.com> — by Google

Official Key Page: https://www.google.com/linuxrepositories/
Error message 
EXPKEYSIG 78BD65473CB3BD13 Google Chrome <linux-packages-keymaster@google.com>

Your distro

Fix commands for Debian

Reinstall the Google signing key

Downloads the current Google signing key, converts it to binary format, and points the Chrome repo entry at it directly — avoiding the deprecated apt-key ring entirely.

Debian — bash
$ curl -fsSL https://dl.google.com/linux/linux_signing_key.pub | gpg --dearmor | sudo tee /usr/share/keyrings/google-chrome.gpg > /dev/null
$ echo "deb [arch=amd64 signed-by=/usr/share/keyrings/google-chrome.gpg] http://dl.google.com/linux/chrome/deb/ stable main" | sudo tee /etc/apt/sources.list.d/google-chrome.list
$ sudo apt-get update

Additional notes

Google rotates its Linux repo signing key periodically. If this fix stops working, check the official page for the current key fingerprint.

After importing the key

Run sudo apt-get update (or your distro's equivalent) again. If successful you should see Hit: lines with no EXPKEYSIG warnings. Still broken? Check that your /etc/apt/sources.list.d/ entry references the correct [signed-by=…] keyring path.