The traffic is encrypted and the key is unknown. While it’s impossible to determine what exact commands were executed in this case, it is still possible to determine if commands were send by the C2 and if results were sent back.
I explain how in this video.
If you have proxy logs in stead of a packet capture, it’s possible to do the same analysis, provided that the proxy logs report how much data (size of HTTP headers and size of data) was exchanged.
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