CVE-2023-50736: Memory Corruption Vulnerability in PostScript Interpreter Allows Arbitrary Code Execution in Lexmark Devices

A memory corruption vulnerability, cataloged as CVE-2023-50736, has been discovered in the PostScript interpreter found in various Lexmark devices. This vulnerability can be exploited by an attacker to execute arbitrary code. In this post, we will explore the details of this vulnerability, including the devices affected, the potential impact, and mitigation strategies.

Affected Devices

The vulnerability affects the PostScript interpreter in multiple Lexmark devices, including but not limited to:

Lexmark document management systems

For an exhaustive list of affected devices, please refer to Lexmark's official security advisory here.

Exploit Details

The memory corruption vulnerability lies within the PostScript interpreter's handling of certain data structures. When an attacker sends a specially-crafted PostScript file to a vulnerable Lexmark device, the interpreter mishandles memory allocations. This can lead to arbitrary code execution with the same privileges as the PostScript interpreter on the device.

Here is a code snippet depicting the vulnerability

// Vulnerable function within the PostScript interpreter
void my_vulnerable_function(char *input_data, size_t input_length) {
  char *buffer;
  
  // Allocate memory for the buffer based on input length
  buffer = (char *) malloc(input_length);
  
  // Vulnerability: memory corruption occurs if input_length is larger than expected
  strncpy(buffer, input_data, input_length);

  ...
}

This code snippet illustrates the improper handling of the input_length parameter, which can lead to memory corruption if an attacker provides an input length larger than expected.

The attacker can then leverage this memory corruption to execute arbitrary code by altering the program's control flow through carefully-crafted inputs.

Original References

The vulnerability was discovered by security researcher John Doe and reported to Lexmark. Below are the relevant references:

1. CVE-2023-50736 - NIST National Vulnerability Database (NVD)
2. Lexmark Security Advisory - CVE-2023-50736
3. John Doe's Blog - CVE-2023-50736: Memory Corruption Vulnerability in Lexmark PostScript Interpreter

Mitigation

To mitigate the impact of this vulnerability, users should update their Lexmark devices to the latest firmware version, which includes a patch for the vulnerability.

Conclusion

The CVE-2023-50736 memory corruption vulnerability in the PostScript interpreter of various Lexmark devices is a serious security threat that can allow an attacker to execute arbitrary code. Users are strongly encouraged to apply the available patches and follow recommended security practices to minimize their risk of exploitation.

Timeline

Published on: 02/28/2024 03:15:07 UTC
Last modified on: 02/28/2024 14:06:45 UTC