This article describes how to decrypt SSL/TLS traffic using a Windows machine.
Step 1: Go to This PC, right-click on an empty space then select Properties from the context menu.
Step 2: Click on the Advanced system settings link on the left side.
Step 3: Click on the Environment Variables button.
Step 4: Click on the New button.
Step 5: Type SSLKEYLOGFILE in the Variable name field.
Step 6: For Variable value, click on the Browse File button and choose the file where to save the TLS/SSL keys. In this example, tlskey.txt has been created.
Step 7: Click on the OK button until all recent window prompts have been closed.
Step 8: Start capture and enable filters in GUI > Network > Packet Capture.
Step 9: Generate TLS/SSL traffic then download the capture and open it on Wireshark.
Step 10: After opening the capture on Wireshark, go to Edit > Preferences.
Step 11: Under Protocols, check and then select TLS (Transport Layer Security).
Step 12: Under (Pre)-Master-Secret log filename, click on the Browse button then choose the TLS key file.
Step 13: Click on the OK button.
Step 14: Decryption of TLS/SSL traffic is completed now.