This article explains how to decrypt RADIUS traffic captured by Wireshark when having authentication issues. Steps in this article explain how to decrypt the traffic to be able to see the username and passcode in plain text.
- Launch the Wireshark app.
- Capture the traffic
- Go to Edit > Preferences
- Click the + next to Protocols to expand the tree
- Scroll down and select RADIUS
- Key in the RADIUS shared secret and click Apply
- The passcode in clear text.
Below is the the packet capture before entering the RADIUS shared secret:
Below is the packet capture after entering the RADIUS shared secret: