In this blog post, we will delve into the details of CVE-2023-24858, a critical security vulnerability reported in Microsoft's PostScript and PCL6 Class Printer Drivers. There is an information disclosure vulnerability in how these drivers handle fonts in Windows, which can be exploited by an attacker to reveal sensitive information from affected systems. This vulnerability has been assigned a base CVSS score of 7.1, indicating its severity. In the following sections, we will discuss the exploit details, available patches/fixes, the affected components, and how to protect your systems from this vulnerability.

Exploit Details

The Microsoft PostScript and PCL6 Class Printer Drivers are responsible for rendering fonts and processing jobs when printing to supported printers. The vulnerability exists due to improper handling of embedded fonts within the print job data. Specifically, an attacker can exploit this by crafting a malicious print job containing a specially formatted font resource, which causes an out-of-bounds read operation when processed by the affected driver. This out-of-bounds read operation grants the attacker access to sensitive information, possibly including user data and system configuration details, from the system's memory.

Code Snippet:

#include <Windows.h>

void trigger_CVE_2023_24858()
    /* Initialize malicious font data */
    unsigned char font_data[] = { ... };

    /* Create malicious print job with embedded font */
    BYTE *pImgData = PrepareMaliciousPrintJob(font_data, sizeof(font_data));

    /* Trigger vulnerability by sending malicious print job to the printer driver */

Affected Components

CVE-2023-24858 affects several components of the Windows operating system, primarily the PostScript and PCL6 Class Printer Drivers. The drivers support multiple generations of printers and are widely used in corporate environments. Windowsversions affected include:

Windows 8.1

For a comprehensive list of affected software, please refer to Microsoft's Security Update Guide.

Mitigations and Available Patches

Microsoft has addressed this vulnerability in the form of security updates as part of their regular Patch Tuesday release cycle. It is strongly recommended that users and administrators apply the necessary patches as soon as possible to secure their systems. The specific patch information for affected Windowsversions can be found at Microsoft's Update Catalog.

Additionally, the following best practices can further aid in reducing the risk associated with this vulnerability:

Implement network segmentation and restrict access to critical resources from untrusted networks.

2. Enforce the principle of least privilege for all accounts and applications to minimize the impact of successful attacks.
3. Ensure that regular backups of sensitive data are taken and stored securely, allowing for easy recovery in case of an actual breach.


CVE-2023-24858 is a severe information disclosure vulnerability affecting Microsoft's PostScript and PCL6 Class Printer Drivers that can allow an attacker to access sensitive information on affected systems. By applying the necessary security updates and adhering to the recommended best practices, users and administrators can effectively secure their systems against the potential exploitation of this vulnerability. Keep your systems patched, and stay vigilant!


Published on: 03/14/2023 17:15:00 UTC
Last modified on: 04/27/2023 19:15:00 UTC