Wireshark-users: Re: [Wireshark-users] Decrypting SSL in existing .pcapng file.
From: Jeff Morriss <jeff.morriss.ws@xxxxxxxxx>
Date: Tue, 20 Oct 2015 10:23:49 -0400
On 10/20/15 08:31, Tim Lewis wrote:
I have a .pcapng capture that was taken from a client machine.  The
traffic I am trying to troubleshoot is all SSL TCP\443.

I have access to the entire SSL cert, private key and all.

Is there a way to decrypt the packets in this .pcapng file?

The wiki has instructions:

https://wiki.wireshark.org/SSL