Byjack

⚠️ Simple POC in Python to show TCP Hijacking for bypassing egress filtering

⚠️ Unfortunately It required administrator access on the victim

Scenario

• RCE through a vulnerability on a service available on TCP/<Port>.
• Egress filtering allow only established sessions on TCP to the Internet.
• Use TCP Hijacking to gain a stable access on the victim from the Internet by using the opened connection on the vulnerable service.

Howto

• Launch server.py on attacker side and note TCP Sequence/Acknowledge number
• Launch client.py on victim side from the RCE to hijack TCP sessions and bypass firewall

Example