CSCwj82736 Bug

[kkachroo]

Can someone from Cisco TAC or Engineering please explain how this issue is replicated?

I am aware about TLS1.3 hybridized support and that sending large size client hello.

But how was out of order achieved while replicating this issue? Because it's a stateful connection and replaying packets won't work.

If anyone can share the detailed replication steps, it will be highly appreciated.

[kkachroo]

TCPreplay and netem didn't help.
I tried scapy earlier and that somewhat addresses this, after making a lot of tweaks in the script.
But when using that, client (source) sends a RST after receiving a SYN-ACK.
I am unable to find a reason for this RST.
Every TCP factor is perfect.

If someone can help and shed some light, that will be great.
I can block this RST from client end, but I want to know the reason why this RST occurs.

Appreciate your help.