CVE-2023-37446: Arbitrary Code Execution Vulnerability in GTKWave 3.3.115

Overview

This blog post examines a significant vulnerability, CVE-2023-37446, which affects GTKWave 3.3.115, widely used software for viewing waveform data produced by digital logic simulators. The vulnerability, which lies in the VCD var definition section of GTKWave, allows for the execution of arbitrary code, posing a severe security threat. This matter is of great concern as it can potentially lead to system compromise or data leakage if a malicious .vcd file is opened, emphasizing the crucial need for immediate mitigation.

Vulnerability Summary

CVE ID: CVE-2023-37446
Severity: High (7.8 CVSS Score)
Attack Vector: Local
Privileges Required: User level
User Interaction: Required
Impact: System compromise, Data leakage

Affected Products

Product | Affected Versions

GTKWave | 3.3.115

How the Exploit Works

The exploit takes advantage of multiple out-of-bounds read vulnerabilities in the VCD var definition section functionality of GTKWave 3.3.115. By crafting a malicious .vcd file, an attacker can cause arbitrary code execution. This vulnerability specifically concerns the out-of-bounds write when triggered via the vcd2lxt2 conversion utility. The victim would need to open the malicious file to trigger these vulnerabilities, potentially leading to system compromise or data leakage.

Conceptual Example Code

Here’s a conceptual example of how the vulnerability might be exploited. This is not actual code, but rather, it serves to illustrate the general idea:

$ gtkwave malicious_file.vcd

In the example above, ‘malicious_file.vcd’ is a specially crafted VCD file that contains the exploit code. When this file is opened using GTKWave, the exploit code is executed, leading to arbitrary code execution.

Mitigation

To mitigate this vulnerability, users are advised to apply the vendor patch as soon as it becomes available. As a temporary measure, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) could aid in preventing exploitation. However, these methods cannot entirely eliminate the vulnerability, and proper patching is the most effective form of protection.