How To: Build Stealth Backdoors

Build Stealth Backdoors


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This is interesting... How can I use this backdoor once it is deployed? Maybe a listener?

All the information is in cd00r.c. To activate the backdoor (it is just a telnet server in this case) you have to send the correct sequence of SYN packets. In line 37 of the code the author suggest this:

./nmap -sS -T Polite -p<port1>,<port2>,<port3> <target>

The sequences of ports to "knock" are defined in line 121 as CDR_PORTS. Order matters.

and once its been sent I telnet in?

Yep. For this to work, the target machine has to have inetd and telnet installed... what is quite unlikely. You can easily change the cdr_open_door function to something that better suits you

Since libpcap uses raw sockets and the backdoor uses libpcap, would that require the backdoor to be run under root privileges?

Hey mate. That's right. Unh0lys0da link has all the details.

Very interesting, thx for sharing.

This is fantastic. I'm looking for a proficient person who clearly understands this, Kali and telecomm's. Please if interested icetip61 AT gmail

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