CVE-2022-41141 - Windscribe Local Privilege Escalation Vulnerability due to Misconfigured OpenSSL

A recently discovered vulnerability, CVE-2022-41141, allows local attackers to escalate their privileges on affected installations of the popular VPN service, Windscribe. In order to exploit this vulnerability, an attacker must first have the ability to execute low-privileged code on the target system. This article will provide a detailed analysis of the vulnerability, including code snippets and original references to help assess the risk and take necessary actions to safeguard your systems.

Vulnerability Details

The core issue behind this vulnerability lies within the configuration of OpenSSL, a widely used software library for secure communication. Windscribe's implementation of OpenSSL loads a configuration file from an unsecured location, making it possible for an attacker to modify this file and subsequently escalate their privileges. If successfully exploited, this vulnerability enables the attacker to execute arbitrary code in the context of SYSTEM, potentially compromising the entire system.

This vulnerability was formerly tracked as ZDI-CAN-16859 and is now assigned the CVE identifier CVE-2022-41141.

Below is a simplified code snippet demonstrating the flaw in Windscribe's implementation of OpenSSL

#include <stdio.h>
#include <openssl/conf.h>

int main(void) {
    OPENSSL_add_all_algorithms_noconf();
    OPENSSL_config(NULL); // Loads configuration file from unsecured location

    // Normal operation continues...
}

This code shows that the OpenSSL library reads its configuration file without performing any checks on the file's location or its permissions. As a result, an attacker can place a malicious configuration in the unsecured location, leading to privilege escalation.

Exploitation

In order to exploit CVE-2022-41141, an attacker must first gain the ability to run low-privileged code on the target system. This can be achieved through various means, such as social engineering attacks, drive-by downloads or an attacker who already has low-privileged access to the targeted machine.

Once the attacker can execute code under limited privileges, they can then modify the OpenSSL configuration file used by Windscribe. This change can instruct the OpenSSL library to load and execute malicious code with higher privileges, effectively escalating their privileges to SYSTEM level.

Mitigation

To protect against this vulnerability, Windscribe should ensure that the OpenSSL configuration files are stored in secured locations, only accessible by trusted users or administrators. This can be achieved by restricting the file permissions and verifying the file's location before loading it.

Moreover, timely patching and updating of systems are essential in reducing the risk of exploit. Users of Windscribe VPN should keep abreast of any updates or patches released by the company and apply them as soon as possible.

Conclusion

CVE-2022-41141 is a serious vulnerability that enables local attackers to escalate their privileges on affected installations of Windscribe. By exploiting this vulnerability, attackers can completely compromise a target system, making it essential for organizations and individuals to assess their exposure and apply necessary security measures. By understanding the nature of the vulnerability, keeping systems up-to-date, and ensuring proper access controls, users can reduce the risk of falling victim to this and similar attacks.

Timeline

Published on: 01/26/2023 18:59:00 UTC
Last modified on: 02/03/2023 19:44:00 UTC