23 - Pentesting Telnet
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Basic Information
Telnet is a network protocol that gives users a UNsecure way to access a computer over a network.
Default port: 23
23/tcp open telnetEnumeration
Banner Grabbing
nc -vn <IP> 23All the interesting enumeration can be performed by nmap:
nmap -n -sV -Pn --script "*telnet* and safe" -p 23 <IP>The script telnet-ntlm-info.nse will obtain NTLM info (Windows versions).
From the telnet RFC: In the TELNET Protocol are various "options" that will be sanctioned and may be used with the "DO, DON'T, WILL, WON'T" structure to allow a user and server to agree to use a more elaborate (or perhaps just different) set of conventions for their TELNET connection. Such options could include changing the character set, the echo mode, etc.
I know it is possible to enumerate this options but I don't know how, so let me know if know how.
Config file
/etc/inetd.conf
/etc/xinetd.d/telnet
/etc/xinetd.d/stelnetHackTricks Automatic Commands
Protocol_Name: Telnet #Protocol Abbreviation if there is one.
Port_Number: 23 #Comma separated if there is more than one.
Protocol_Description: Telnet #Protocol Abbreviation Spelled out
Entry_1:
Name: Notes
Description: Notes for t=Telnet
Note: |
wireshark to hear creds being passed
tcp.port == 23 and ip.addr != myip
https://book.hacktricks.xyz/pentesting/pentesting-telnet
Entry_2:
Name: Banner Grab
Description: Grab Telnet Banner
Command: nc -vn {IP} 23
Entry_3:
Name: Nmap with scripts
Description: Run nmap scripts for telnet
Command: nmap -n -sV -Pn --script "*telnet*" -p 23 {IP}
Entry_4:
Name: consoleless mfs enumeration
Description: Telnet enumeration without the need to run msfconsole
Note: sourced from https://github.com/carlospolop/legion
Command: msfconsole -q -x 'use auxiliary/scanner/telnet/telnet_version; set RHOSTS {IP}; set RPORT 23; run; exit' && msfconsole -q -x 'use auxiliary/scanner/telnet/brocade_enable_login; set RHOSTS {IP}; set RPORT 23; run; exit' && msfconsole -q -x 'use auxiliary/scanner/telnet/telnet_encrypt_overflow; set RHOSTS {IP}; set RPORT 23; run; exit' && msfconsole -q -x 'use auxiliary/scanner/telnet/telnet_ruggedcom; set RHOSTS {IP}; set RPORT 23; run; exit'
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