Overview
The Common Vulnerabilities and Exposures (CVE) system has recently identified a critical security flaw, designated CVE-2023-38620, within the VZT facgeometry parsing functionality of GTKWave, version 3.3.115, a popular open-source waveform viewer. The issue present is a series of multiple integer overflow vulnerabilities, which may lead to arbitrary code execution upon opening a maliciously crafted .vzt file. This vulnerability is particularly concerning as it could potentially lead to system compromise or data leakage, posing a significant threat to any organization utilizing the affected software.
Vulnerability Summary
CVE ID: CVE-2023-38620
Severity: High (CVSS: 7.8)
Attack Vector: Network
Privileges Required: None
User Interaction: Required
Impact: Potential system compromise or data leakage
Affected Products
No phone number, email, or personal info required.
Product | Affected Versions
GTKWave | 3.3.115
How the Exploit Works
The vulnerabilities exist due to an integer overflow when allocating the ‘lsb’ array in the VZT facgeometry parsing functionality of GTKWave. This can occur when a user opens a specifically crafted .vzt file, which can then lead to arbitrary code execution. An attacker who successfully exploits this vulnerability could execute arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system.
Conceptual Example Code
While an exact example of this exploit cannot be provided due to responsible disclosure practices, the conceptual exploit would involve creating a malicious .vzt file that would cause an integer overflow when opened with GTKWave. The file would be designed to trigger the overflow in the ‘lsb’ array allocation, which would then allow for the execution of arbitrary code.
// Pseudocode
malicious_file.vzt = {
// crafted data to cause integer overflow
}Then, this file would be delivered to the victim, who would open it with GTKWave, triggering the vulnerability.
Mitigation Guidance
To protect your systems from this vulnerability, it is recommended to apply the vendor patch as soon as it becomes available. If the patch is not yet available or cannot be applied immediately, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can provide temporary mitigation. Additionally, users should be cautious when opening .vzt files from unknown sources and ensure their systems are updated with the latest security patches and updates.