Wireshark Decrypt SSL Client Certificate

Deciphering SSL client certificates can be a daunting task, especially when working with encryption methods like Wireshark. In this article, we will explore how to decrypt SSL client certificates using Wireshark.

To begin with, we need to set up logging for our client utility or browser. This involves creating an empty file, in this case, `tlskey.log`, and enabling logging for debugging purposes. Once we have done this, we can proceed to use the `curl` command with the SSLKEYLOGFILE parameter at the beginning.

The second step is to capture packets using Wireshark. We will need to analyze these packets to find the encrypted key used by the client to establish a secure connection with the server. To do this, we can use Wireshark's decryption feature to decrypt the captured packets and view the SSL keys in the comments section.

One way to achieve this is to use Keytool to generate the key/cert and run a small HTTP/2 server with this cert/key. In my case, I used the following command to generate the key:

`Keytool -genkey -alias undertow -storetype PKCS12 -keyalg RSA -keysize 2048 -keystore keystore.p12 -dname 'CN=localhost, OU=localhost, O=localhost, L=Zhengzhou, ST=Henan, C=CN'`

However, when I tried to capture packets using Wireshark and decrypt them using the generated key, I didn't see any comments or keys in the capture file. This led me to search for alternative methods.

After some research, I discovered that the SSL keys are not stored directly in the capture file but rather need to be extracted from it. One way to do this is by using Wireshark's decryption feature and selecting the `ssl.keylog` option.

Once you have selected this option, Wireshark will generate a log file containing the SSL key used by the client. You can then use this log file to decrypt the captured packets and view the SSL keys in the comments section of the capture file.

In conclusion, deciphering SSL client certificates using Wireshark requires some technical expertise and knowledge of encryption methods. However, with these steps, you should be able to extract the SSL key used by the client and decrypt the captured packets.

Wireshark decrypt ssl client certificate