A critical out-of-bounds vulnerability (CVE-2025-1268) has been identified in the EMF Recode processing of multiple Generic Plus Printer Drivers, including the PCL6, UFR II, LIPS4, LIPSLX, and PS Printer Drivers. This vulnerability, if exploited, could lead to unauthorized access and potential control over compromised systems. In this long read post, we will delve deep into the exploit details, code snippets, and original references associated with this security flaw.

The vulnerability

The affected printer drivers could contain a buffer overflow vulnerability due to insufficient validation of user-supplied data while processing Enhanced Metafile Format (EMF) records. The vulnerability occurs when parsing specially crafted EMF files, which can lead to an out-of-bounds write operation, potentially allowing an attacker to execute arbitrary code on the victim system.

An example of the vulnerable code in the affected printer drivers may look like the following

#include "stdafx.h"
#include "emf.h"

void ProcessEMFRecord(HANDLE hPrinter, PEMFRecord pRecord) {
  // Pseudo code
  switch (pRecord->iType) {
    case EMR_ALPHABLEND: {
      PEMRAlphaBlend alphaBlend = (PEMRAlphaBlend)pRecord;
      // Vulnerable function used here
      HANDLE hBitmap =
          CreateDIBitmapFromEMFRecord(alphaBlend->dwRop, alphaBlend->xOff, alphaBlend->yOff);
      DrawDIBitmap(hPrinter, hBitmap);
      break;
    }
  }
}

In the above code, the issue arises due to improper handling of the values provided in the EMR_ALPHABLEND record, which can cause a buffer overflow vulnerability when the CreateDIBitmapFromEMFRecord function is called.

Exploit details

An attacker can exploit this vulnerability by sending a malicious EMF file to the victim that will be processed by the affected printer driver. The specially crafted EMF file will contain a large value for the xOff and yOff parameters, causing an out-of-bounds memory write operation. Execution of arbitrary code can be achieved through a carefully constructed payload embedded within the malicious EMF file.

The details of this vulnerability (CVE-2025-1268) can be found in the following original references

1. NVD - CVE-2025-1268
2. MITRE CVE Dictionary - CVE-2025-1268

Mitigation

To mitigate this vulnerability, it is recommended to update the affected Generic Plus Printer Drivers to the latest versions, which includes patches to address the out-of-bounds vulnerability. The updated versions can be found on the official websites of the respective vendors.

Conclusion

This deep dive into the CVE-2025-1268 vulnerability demonstrates the potential impact an out-of-bounds vulnerability can have on multiple Generic Plus Printer Drivers. By understanding the exploit details, code snippets, and original references, we can better protect our systems and ensure that the necessary patches are in place. Recognizing and addressing vulnerabilities like this is an essential part of maintaining a secure computing environment.

Timeline

Published on: 03/31/2025 02:15:17 UTC
Last modified on: 04/01/2025 20:26:30 UTC