Security researchers have discovered a vulnerability in the tiffcp utility - a widely used tool that is part of the libtiff package. The vulnerability, tracked as CVE-2023-6228, deals with a critical heap-based buffer overflow. This issue may cause a processing issue on a crafted TIFF file that can lead to an application crash. In this article, we provide a detailed analysis of this vulnerability, including code snippets and links to original references, as well as details about the exploitation process.


The libtiff package is an open-source library that provides support for the Tag Image File Format (TIFF), a popular format for storing images. The 'tiffcp' utility distributed with this package is used for copying and converting TIFF files, thus making it a popular target for attackers interested in exploiting vulnerabilities in TIFF-related software.

Exploit Details

The vulnerability stems from a heap-based buffer overflow issue found in the tiffcp utility while processing a specially crafted TIFF file. An attacker can craft a malicious TIFF file that, when processed by the user running tiffcp, could trigger this vulnerability, causing a buffer overflow that could crash the application.

To better understand the vulnerability, let's take a look at the code snippet responsible for the issue, taken from the libtiff repository:

void tiffcp(TIFF* in, TIFF* out) {
  uint32* raster;
  raster = (uint32*)_TIFFmalloc(input_width * input_length * sizeof (uint32));
  TIFFReadRGBAImage(in, input_width, input_length, raster, );
  TIFFWriteEncodedStrip(out, , raster, TIFFScanlineSize(in));

In the code snippet, the _TIFFmalloc function allocates memory for the raster buffer, which is then used to store the pixel data of the input TIFF file. The issue arises from the insufficient size of the allocated raster buffer, which can be smaller than the memory accessed when using the TIFFWriteEncodedStrip function. As a result, when the application writes data to the buffer, it can overflow the heap, causing a crash.

The following resources provide further information on this vulnerability

1. Libtiff GitHub repository:
2. Libtiff official website:
3. CVE Details:


The CVE-2023-6228 vulnerability is a critical heap-based buffer overflow issue in the tiffcp utility from the libtiff package. Attackers can exploit this vulnerability to cause an application crash, making it crucial for affected users to take immediate remediation steps. By staying informed about such issues and promptly applying security patches, users can significantly reduce the risk of exploitation.


Published on: 12/18/2023 14:15:11 UTC
Last modified on: 12/29/2023 07:15:10 UTC