CVE-2023-36705 - Windows Installer Elevation of Privilege Vulnerability: Understanding the Exploit and Mitigating Risks

A new vulnerability, tracked as CVE-2023-36705, has been discovered in the Windows Installer, which can be exploited to allow potential attackers to gain elevated privileges on the target system. In this post, we will explore the details of this vulnerability, including its origin, how it can be exploited, and what steps can be taken to mitigate the risks it poses. We'll also discuss the code snippets related to this vulnerability to provide a better understanding of the issue at hand.

Details of CVE-2023-36705

CVE-2023-36705 is a security bug that affects all versions of the Windows operating system. It is a type of Elevation of Privilege (EoP) vulnerability, which means that it allows an attacker to exploit the system and gain a higher level of access than they should have. In this case, the vulnerability lies in the Windows Installer service.

Original Reference Links

1. Microsoft's Security Advisory on CVE-2023-36705
2. National Vulnerability Database Entry for CVE-2023-36705

Exploit Details

The Windows Installer service is responsible for installing, repairing, and uninstalling software on a Windows system. Due to incorrect handling of custom actions in the installer, an attacker who has access to a vulnerable system can execute malicious code with elevated privileges. This may allow them to perform actions such as creating administrative accounts, disabling security features, or installing additional malicious software.

The exploit for this vulnerability involves creating a specially crafted Installer Package, which contains a malicious payload as a custom action. When the package is executed, the Windows Installer service will execute the payload with elevated privileges, effectively giving the attacker control over the target system.

Code Snippet Example

<CustomAction Id="ElevatedPayloadExecution"
              Directory="TARGETDIR"
              ExeCommand="[SystemFolder]cmd.exe /C [ElevatedPayloadPath]"
              Execute="deferred"
              Impersonate="no" />

In this example, the custom action (ElevatedPayloadExecution) contains a malicious payload that is executed with elevated privileges when the installation process takes place. This would allow the attacker to execute additional malicious code on the target system.

To protect your systems from this vulnerability, the following steps are recommended

1. Apply Security Patches: Microsoft has released patches to address this vulnerability in all affected versions of Windows. Ensure that you update your systems as soon as possible to prevent potential exploits.
* Security Update for Windows

2. Monitor for Suspicious Installations: Keep an eye on any attempts to install software on your systems, especially from unknown sources or packages with suspicious custom actions. Implementing application whitelisting and ensuring that only approved software can be installed can also help prevent exploitation of this vulnerability.

3. Restrict Access: Restricting user access to systems and enforcing the principle of least privilege can help limit the potential damage caused by this vulnerability. Ensure that only authorized administrators can perform software installations and updates.

Conclusion

CVE-2023-36705 is a serious security vulnerability affecting the Windows Installer service that can potentially allow attackers to gain elevated privileges on vulnerable systems. By understanding the nature of the exploit, applying the appropriate security patches, and following best practices for system security, you can reduce the risk posed by this vulnerability and help protect your systems from potential attacks.

Timeline

Published on: 11/14/2023 18:15:50 UTC
Last modified on: 11/20/2023 19:55:03 UTC