cheatsheets/cheatsheets/security/pentesting/snmp-enumeration.md

---

title: SNMP Enumeration categories: [cheatsheets]

tags: [pentesting]

SNMP Enumeration

What is SNMP?

• SNMP: Network Management Protocol
• Transport: UDP
• Port: 161

Used for managing network devices like computers, printers, switches via UDP/IP.

SNMP has three major components:

1) Managed Device:

Device/Host (Node) with an enabled SNMP service. Can be Computers, Switches, Printers, Routers

2) Agent:

Software that runs on a managed device. Converts information of the Node into a SNMP compatible format.

4) Network Management System (NMS):

Software System that is used for monitoring the network devices.

An agent can be queried for different information via SNMP. The agent provides a read-/writeable database, the so called management information base (MiB). This DB is hierarcically organized and contains objects (recognized by object identifier, OIDs).

For authentication purpose, a so called community string is used. In early versions of SNMP the community string is send in plaintext over the network.

Default community string: public

Enumeration

Tools

• snmp-check
• snmpwalk
• onesixtyone

Multiple Information can be queried

• snmp-check + sample output

• Things that can be queried

  • System information
  • Network interfaces
  • Network IP
  • Routing information
  • TCP connections and listening ports
  • Network services
  • Processes

  • ...

    sh> snmp-check <ip>
    
    snmp-check v1.9 - SNMP enumerator
    Copyright (c) 2005-2015 by Matteo Cantoni (www.nothink.org)
    
    [+] Try to connect to 10.11.1.128:161 using SNMPv1 and community 'public'
    
    [*] System information:
    
    Host IP address               : 10.11.1.128
    Hostname                      : DJ
    Description                   : Hardware: x86 Family 6 Model 15 Stepping 2 AT/AT COMPATIBLE - Software: Windows 2000 Version 5.0 (Build 2195 Uniprocessor Free)
    Contact                       : HASH(0xDEADBEF)
    Location                      : -
    Uptime snmp                   : 5 days, 20:52:20.00
    Uptime system                 : 14:04:36.46
    System date                   : 2019-9-29 15:44:29.4
    Domain                        : WORKGROUP
    
    [*] Network interfaces:
    
    [...]
    
    [*] Network IP:
    
    [...]
    
    [*] Routing information:
    
    [...]
    
    [*] TCP connections and listening ports:
    
    [...]
    
    [*] Network services:
    
    [...]
    
    [*] Processes:
    
    [...]