Overview
In this blog post, we delve into the critical details of a recently discovered vulnerability, CVE-2023-39273, affecting the LXT2 facgeometry parsing functionality of GTKWave version 3.3.115. This vulnerability is particularly concerning due to its potential to allow arbitrary code execution, which could lead to a full system compromise or data leakage. Because GTKWave is a widely used waveform viewer in the digital design industry, this vulnerability could lead to significant disruptions and security issues if not properly addressed.
Vulnerability Summary
CVE ID: CVE-2023-39273
Severity: High (CVSS 7.8)
Attack Vector: Local
Privileges Required: Low
User Interaction: Required
Impact: Potential system compromise and data leakage
Affected Products
Share secrets securely
Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.
Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.
- • Encrypted identity
- • Private Spaces for organizations and teams
- • End-to-end encrypted chat, calls, files, and notes
- • Sensitive AI work and protected collaboration
- • Built for information that cannot leak
Our mission is to secure human work alongside AI.
Product | Affected Versions
GTKWave | 3.3.115
How the Exploit Works
The vulnerability resides in the LXT2 facgeometry parsing functionality of GTKWave. It is based on integer overflow vulnerabilities that could occur when allocating the `flags` array. An attacker can craft a malicious .lxt2 file that, when opened by a victim, triggers the integer overflow. This flaw could potentially lead to memory corruption, which in turn could be exploited to execute arbitrary code on the victim’s system.
Conceptual Example Code
Below is a conceptual example of how an attacker might craft a malicious .lxt2 file to exploit this vulnerability:
#include <stdio.h>
#include <stdlib.h>
int main() {
FILE *file;
unsigned long long int large_value = 0xFFFFFFFFFFFFFFFF;
file = fopen("malicious.lxt2", "w");
if (file == NULL) {
printf("Error opening file\n");
return -1;
}
fwrite(&large_value, sizeof(large_value), 1, file);
fclose(file);
return 0;
}In this simplified example, an attacker crafts a .lxt2 file that contains an exceedingly large integer value. When GTKWave attempts to allocate the `flags` array based on this value, it results in an integer overflow and potential memory corruption.
Recommended Mitigation
Users of the affected GTKWave version are strongly advised to apply the vendor-supplied patch as soon as possible to mitigate this vulnerability. In cases where immediate patching is not possible, employing a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as temporary mitigation, but these should not be considered a long-term solution. As always, caution should be exercised when opening files from unknown sources.