CVE-2023-37445: Critical Out-of-Bounds Read Vulnerabilities in GTKWave

Overview

This blog post explores a critical vulnerability identified as CVE-2023-37445, which affects the VCD var definition section functionality in GTKWave 3.3.115. The software’s users are susceptible to this vulnerability, which can lead to devastating consequences such as arbitrary code execution. The CVE-2023-37445 vulnerability underscores the importance of diligent software development and robust cybersecurity practices, given its potential to compromise systems and leak sensitive data if successfully exploited.

Vulnerability Summary

CVE ID: CVE-2023-37445
Severity: High (7.8 CVSS Score)
Attack Vector: Local
Privileges Required: None
User Interaction: Required
Impact: System compromise, potential data leakage

Affected Products

Product | Affected Versions

GTKWave | 3.3.115

How the Exploit Works

The vulnerability arises from multiple out-of-bounds read vulnerabilities existing in the VCD var definition section of GTKWave. An attacker can craft a malicious .vcd file containing specific codes that exploit these vulnerabilities. Upon opening this file, the victim’s system triggers an out-of-bounds write operation via the vcd2vzt conversion utility, which can lead to arbitrary code execution.

Conceptual Example Code

Consider the following conceptual code block:

# A bash script to generate a malicious .vcd file
echo 'Exploit code here...' > exploit.vcd
# A command to convert .vcd to .vzt using vcd2vzt utility
vcd2vzt exploit.vcd exploit.vzt

In this example, the attacker first generates a malicious .vcd file containing the exploitation code. Next, the attacker uses the vcd2vzt utility to convert the .vcd file to .vzt format. When the victim opens the resulting .vzt file using GTKWave, the out-of-bounds write operation is triggered, leading to the execution of the attacker’s arbitrary code.

Mitigation Guidance

Users affected by this vulnerability should consider applying the vendor patch. If the patch is not available, solutions such as using Web Application Firewalls (WAF) or Intrusion Detection Systems (IDS) could serve as temporary mitigation against potential attacks exploiting this vulnerability. Always remember to keep your software up-to-date as a general principle for maintaining cybersecurity hygiene.