CVE-2023-35997: Arbitrary Code Execution Vulnerability in GTKWave

Overview

The vulnerability CVE-2023-35997 has been identified in the software GTKWave 3.3.115 and poses a serious threat to system security. This vulnerability is caused by multiple improper array index validation vulnerabilities within the fstReaderIterBlocks2 tdelta functionality of GTKWave. The exploitation of these vulnerabilities could result in arbitrary code execution, potentially leading to system compromise and data leakage. The severity of this breach makes it of high importance to any organization or individual using this software.

Vulnerability Summary

CVE ID: CVE-2023-35997
Severity: High (7.8)
Attack Vector: File
Privileges Required: None
User Interaction: Required
Impact: System compromise or data leakage

Affected Products

Product | Affected Versions

GTKWave | 3.3.115

How the Exploit Works

The exploit works by targeting the tdelta functionality in the fstReaderIterBlocks2 of GTKWave. It is able to do this through the use of a specially crafted .fst file. When a victim opens this file, improper array index validation vulnerabilities are triggered, potentially leading to arbitrary code execution. This is especially concerning when signal_lens is 2 or more.

Conceptual Example Code

While an actual code exploiting this vulnerability is not provided for safety reasons, a conceptual example might look something like this:

# Create a malicious .fst file
echo "[malicious code]" > exploit.fst
# Use the malicious .fst file with GTKWave
gtkwave exploit.fst

This pseudocode suggests the creation of a malicious .fst file containing code designed to exploit the improper array index validation vulnerabilities in the tdelta functionality of fstReaderIterBlocks2. The second line simulates a victim opening the malicious .fst file with GTKWave, triggering the vulnerability and potentially leading to arbitrary code execution.

Mitigation

Users are advised to apply the vendor patch as soon as it’s available. In the meantime, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as a temporary mitigation. Regularly updating your software and maintaining good cybersecurity practices can also reduce the risk of falling victim to such vulnerabilities.