CVE-2023-46805: Authentication Bypass Vulnerability in Ivanti ICS 9.x, 22.x and Ivanti Policy Secure

A critical security vulnerability, tracked as CVE-2023-46805, has been discovered in the web component of Ivanti ICS 9.x, 22.x and Ivanti Policy Secure. This vulnerability allows an attacker to bypass authentication checks and access restricted resources without proper authorization. In this long-read post, we will cover the details of this vulnerability, including a code snippet showcasing the issue, links to original references, and an explanation of how an attacker could potentially exploit it. Please note that this information is provided solely for educational and awareness purposes, and any malicious use of this information is strictly prohibited.

Vulnerability Details

The vulnerability resides in the web component of Ivanti ICS 9.x, 22.x and Ivanti Policy Secure, specifically within the authentication control checks. When not properly configured, an attacker can craft malicious requests to the web server, bypassing these authentication checks and gaining unauthorized access to restricted resources.

Imagine a web server that is supposed to enforce authentication checks to grant access only to authorized users. In this case, the affected Ivanti products fail to validate user-supplied input during the authentication process, allowing unauthorized users to potentially access sensitive resources.

Here's a sample code snippet that demonstrates the issue in a more general way

def authenticate(request):
    token = request.get("token", None)
    if not token:
        # Missing token
        return False
    
    # Validate token
    valid_token = check_token(token)
    
    if valid_token:
        return True
    else:
        return False

def check_token(token):
    # This function should have additional security measures like checking token signature, expiration, etc.
    # The vulnerability stems from the lack of these additional checks.
    if token in valid_tokens:
        return True
    else:
        return False

def restricted_resource(request):
    if authenticate(request):
        return "Access granted to sensitive data"
    else:
        return "Access denied"

In the code snippet above, the function authenticate() checks whether a token is present in the incoming request and proceeds to validate the token using the check_token() function. However, the check_token() function lacks additional security measures like checking token signature, expiration, etc. As a result, an attacker could craft a request with a fake token that gets treated as valid, bypassing the authentication check and granting unauthorized access.

Send the malicious request to the target server.

4. If successful, the sever will respond with the restricted content, granting unauthorized access to the attacker.

The following links provide more information about this vulnerability

- Ivanti Security Advisory - CVE-2023-46805
- National Vulnerability Database (NVD) - CVE-2023-46805

Mitigation and Remediation

To mitigate and remediate this vulnerability, Ivanti has released security updates for Ivanti ICS and Ivanti Policy Secure. Users of the affected software are advised to apply these updates as soon as possible to protect their systems from potential attacks.

In conclusion, the CVE-2023-46805 vulnerability is a critical issue that affects Ivanti ICS and Ivanti Policy Secure. By understanding how this vulnerability works and how attackers could potentially exploit it, we can take the necessary steps to ensure our systems are secure. Always keep your software up-to-date and follow security best practices to minimize the risk of compromise.

Timeline

Published on: 01/12/2024 17:15:09 UTC
Last modified on: 01/19/2024 02:00:01 UTC