alt Hacker NewsHow do you punch trough firewalls? You have to manually open them, punching through firewall would be a firewall vulnerability.
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mightyham • yesterday at 6:09 PM
Typically firewalls will record the src and dst header values of outbound IP packets then temporarily allows inbound IP packets that have those values flipped.
This is a common function of uPnP, which I've seen as features in router config pages since the mid 2000s.
https://en.wikipedia.org/wiki/Universal_Plug_and_Play#NAT_tr...