# 161 - SNMP

**Simple Network Management Protocol (SNMP)** runs over UDP port `161` and is used to monitor and manage network devices like routers and servers. It allows querying for system info (e.g. uptime, CPU, interfaces) and is commonly used in network monitoring tools. If misconfigured—especially with default "public" community strings—it can leak sensitive data or be abused in DDoS attacks.

{% tabs %}
{% tab title="snmpwalk" %}
Enumerate public strings:

```bash
snmpwalk -v2c -c public <target>
```

Dig deeper with specific OIDs:

```bash
# System info
snmpwalk -v2c -c public <target> 1.3.6.1.2.1.1

# NICs
snmpwalk -v2c -c public <target> 1.3.6.1.2.1.2.2

# Users
snmpwalk -v2c -c public <target> 1.3.6.1.4.1

# Running processes
snmpwalk -v2c -c public <target> 1.3.6.1.2.1.25.4.2.1.2

# Open TCP ports
snmpwalk -v2c -c public <target> 1.3.6.1.2.1.6.13.1.3
```

Or grep for keywords:

```bash
snmpwalk -v2c -c public <target> | grep -Ei 'user|admin|name|password|pass'
```

{% endtab %}

{% tab title="onesixtyone" %}
Brute-force community strings:

{% code overflow="wrap" %}

```bash
onesixtyone -c /usr/share/seclists/Discovery/SNMP/snmp-onesixtyone.txt <target>
onesixtyone -c /usr/share/wordlists/metasploit/snmp_default_pass.txt <target>

```

{% endcode %}
{% endtab %}

{% tab title="nmap" %}
asd

{% code overflow="wrap" %}

```bash
sudo nmap -sU -p 161 --script snmp-info,snmp-interfaces,snmp-processes <target>
```

{% endcode %}
{% endtab %}

{% tab title="snmp-check" %}

```bash
snmp-check -c public <target>
```

{% endtab %}
{% endtabs %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://x7331.gitbook.io/boxes/services/udp/snmp-161.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.