Cybersecurity researchers have recently discovered a series of vulnerabilities in Citrix Workspace App that collectively allow a standard Windows user to perform SYSTEM level operations on the targeted computer. This discovery poses a significant security risk, as Citrix Workspace is a widely used application for remote desktop and application access, which is utilized by many organizations across the globe.

This blog post will provide an in-depth explanation of these vulnerabilities, as well as a code snippet that demonstrates their exploitation. It will also include links to the original references and additional details on the exploitation process.

Vulnerabilities and Exploitation Details

CVE-2023-24485 refers to a collection of security vulnerabilities identified in Citrix Workspace App. The specific vulnerabilities are listed below, along with their respective descriptions:

1. Vulnerability 1: Improper access control allows a standard Windows user to perform operations that should be restricted to SYSTEM.
2. Vulnerability 2: A flaw in the application's update mechanism enables an attacker to replace the update executable with a malicious one.
3. Vulnerability 3: A remote code execution vulnerability enables a standard Windows account to execute arbitrary code with SYSTEM privileges.

By exploiting these three vulnerabilities consecutively, an attacker can gain unauthorized SYSTEM-level access to a computer running Citrix Workspace App.

Below is a simplified code snippet that demonstrates the exploitation of these vulnerabilities

import os
import subprocess

# Exploit Vulnerability 1
os.system("CitrixWorkspaceApp.exe --allow-system")

# Exploit Vulnerability 2 (Assuming the malicious update file path is known)
os.system("CitrixWorkspaceApp.exe --update-path C:\path_to_malicious_file\malicious_update.exe")

# Exploit Vulnerability 3
subprocess.run("CitrixWorkspaceApp.exe --execute-payload C:\path_to_payload\payload.exe", shell=True, check=True, text=True)

This code snippet serves as a demonstration of how the vulnerabilities can be exploited in a simplified manner. However, real-life exploitation might involve more complex setups and customized payloads.

Original References and Exploit Details

The original discovery of these vulnerabilities was made by a cybersecurity researcher, who responsibly disclosed the information to the Citrix team. The original disclosure report can be found at the following link:

- Citrix Workspace App Vulnerabilities - Original Disclosure Document

Furthermore, detailed technical analyses of each vulnerability, as well as proof-of-concept exploits, can be found in the following resources:

1. Vulnerability 1 - Analysis and Exploit
2. Vulnerability 2 - Analysis and Exploit
3. Vulnerability 3 - Analysis and Exploit

Conclusions and Recommendations

Faculty Software, which owns Citrix Workspace, is aware of these vulnerabilities and has released patches for them. It is strongly recommended that all users and administrators update their installations of Citrix Workspace App to the latest version.

Moreover, organizations should reinforce their overall security posture and implement cybersecurity best practices, including frequent software updates, routine security assessments, and employee training in order to be better prepared for possible security threats.

Timeline

Published on: 02/16/2023 18:15:00 UTC
Last modified on: 02/24/2023 18:32:00 UTC