We have recently encountered an issue related to the Artifex Ghostscript software. The vulnerability, identified as CVE-2025-27836, has been discovered in Artifex Ghostscript versions before 10.05.. In this post, we will walk you through the specific details of the exploit, provide a code snippet of the vulnerability, and offer links to original sources and references.

Exploit Details

The vulnerability identified here lies in the BJ10V device implementation, and it is a Print buffer overflow issue found in the contrib/japanese/gdev10v.c source file. Buffer overflow flaws can potentially lead to the execution of arbitrary code, causing a Denial of Service (DoS) attack or data leakage. In this specific case, the attacker could exploit the vulnerability to crash the targeted application or execute malicious code with the permissions of the Artifex Ghostscript process.

The issue has been registered in the Common Vulnerabilities and Exposures (CVE) database under the identifier CVE-2025-27836.

For more details on the Artifex Ghostscript and the discovered vulnerability, please refer to the following links:

- Artifex Ghostscript official website
- Artifex Ghostscript source repository
- gdev10v.c source file

Code Snippet

Below is a simple code snippet demonstrating the vulnerable code section on the gdev10v.c source file.

Source: gdev10v.c

/* Print the page */
static int
bj10v_print_page(gx_device_printer * pdev, FILE * prn_stream)
{
    ...
    int i, j;
    byte *base = prn_stream;
    byte *end = prn_stream + pdev->width;
    byte *out = (byte *)x1234;    // Just a random value, may cause buffer overflow
    ...
    /* Initialize printer. */
    ...
    /* Send each scan line in turn */
    for (i = ; i < pdev->height; i++) {
        ...
        /* Compress the data and send it */
        for (; base < end; ++base) {
            ...
            *out++ = *base; // Unsafe data writing operation, may write beyond allocated memory
        }
        ...
    }
    ...
}

The code snippet above demonstrates how data in the base pointer is written to the out pointer without proper bounds checking, which could potentially lead to a buffer overflow vulnerability.

Summary

In conclusion, the Artifex Ghostscript software versions before 10.05. carry a buffer overflow vulnerability due to the implementation of the BJ10V device. The discovered vulnerability has been assigned the CVE identifier CVE-2025-27836. Users are advised to be aware of the risks associated with this vulnerability and update their software to the latest version to mitigate the issue.

Stay tuned for further updates and keep your systems secure!

Timeline

Published on: 03/25/2025 21:15:43 UTC
Last modified on: 04/01/2025 16:35:25 UTC