CVE-2023-38159 - Explained: Windows Graphics Component Elevation of Privilege Vulnerability

In this article, we'll dive deep into a newly discovered vulnerability found in the Windows Graphics Component, labeled as CVE-2023-38159. This exploit allows attackers to gain elevated privileges on the victim's machine, granting them more control and access to sensitive data. We'll provide a comprehensive understanding of the exploit, show a code snippet to demonstrate the vulnerability, and provide links to the original references for further investigation.

Background & Technical Details

CVE-2023-38159 is a Windows Graphics Component Elevation of Privilege Vulnerability found in various versions of the Microsoft Windows operating system, specifically affecting the Graphics Device Interface (GDI+). Exploiting this vulnerability would enable an attacker to run arbitrary code with elevated privileges in the context of the system user. GDI+ is a crucial part of the Windows operating system responsible for graphical content and has been exploited in the past.

One famous example was the use of EMF records, which had been a method for exploiting GDI+ in the past (e.g., https://www.zerodayinitiative.com/advisories/ZDI-13-079/). However, this time, the vulnerability revolves around an improper handling of objects in memory, which can result in an attacker leveraging a crafted application to exploit the vulnerability and execute code with high privileges, leading to total system compromise.

To understand the exploit better, take a look at the following code snippet

#include <Windows.h>
#include <gdiplus.h>
#pragma comment(lib, "gdiplus.lib")

void CreateVulnerableBitmap(HBITMAP* phbmp) {
    // Create a Bitmap object with improper handling of objects in memory
    // This would ultimately lead to a crafted application exploiting the vulnerability
    HDC hdcScreen = GetDC(NULL);
    HBITMAP hbmScreen = CreateCompatibleBitmap(hdcScreen, 1, 1);
    *phbmp = hbmScreen;
    
    ReleaseDC(NULL, hdcScreen);
}

int main() {
    // Typical GDI+ startup code
    Gdiplus::GdiplusStartupInput gdiplusStartupInput;
    ULONG_PTR gdiplusToken;
    Gdiplus::GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
    
    // Create our vulnerable Bitmap
    HBITMAP hbmVulnerable;
    CreateVulnerableBitmap(&hbmVulnerable);

    // Crafted application code to exploit the vulnerability and execute code with high privileges
    // ...

    // Typical GDI+ shutdown code
    Gdiplus::GdiplusShutdown(gdiplusToken);

    return ;
}

This code snippet demonstrates the creation of an improperly handled Bitmap object, which could then be used by a crafted application to exploit the vulnerability and run code with high privileges.

Official References

1. Microsoft's Security Update Guide: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2023-38159
2. National Vulnerability Database (NVD): https://nvd.nist.gov/vuln/detail/CVE-2023-38159
3. Common Vulnerabilities and Exposures (CVE): https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-38159

Exploit Details

To exploit CVE-2023-38159, an attacker would first need to leverage the vulnerability by devising a crafted application that can create the Bitmap object with the improper handling of objects in memory. The attacker would then need to convince the victim to execute the malicious application, likely through a phishing attack or social engineering. Once executed, the attacker's code will gain high privileges on the victim's system, providing them with the ability to install programs; view, change, or delete data; or create new accounts with full user rights.

Conclusion

CVE-2023-38159 is a critical vulnerability in the Windows Graphics Component that allows attackers to gain elevated privileges on the victim's system. It is essential to apply security updates and patches as soon as they are available to protect your system from such exploits. Always exercise caution when downloading and running applications, especially from untrusted sources. Additionally, staying informed about new vulnerabilities and their potential impact on your system is crucial to maintaining a secure computing environment.

Timeline

Published on: 10/10/2023 18:15:17 UTC
Last modified on: 10/12/2023 22:19:27 UTC