FTP Bounce attack - Scan

FTP Bounce - Scanning

Manual

1. Connect to vulnerable FTP

2. Use PORTor EPRT(but only 1 of them) to make it establish a connection with the <IP:Port> you want to scan:

   PORT 172,32,80,80,0,8080 EPRT |2|172.32.80.80|8080|

3. Use LIST(this will just send to the connected <IP:Port> the list of current files in the FTP folder) and check for the possible responses: 150 File status okay (This means the port is open) or 425 No connection established (This means the port is closed) 1. Instead of LIST you could also use RETR /file/in/ftp and look for similar Open/Close responses.

Example Using PORT (port 8080 of 172.32.80.80 is open and port 7777 is closed):

Same example using EPRT(authentication omitted in the image):

Open port using EPRT instead of LIST (different env)

nmap

nmap -b <name>:<pass>@<ftp_server> <victim>
nmap -Pn -v -p 21,80 -b ftp:ftp@10.2.1.5 127.0.0.1 #Scan ports 21,80 of the FTP
nmap -v -p 21,22,445,80,443 -b ftp:ftp@10.2.1.5 192.168.0.1/24 #Scan the internal network (of the FTP) ports 21,22,445,80,443