CVE-2023-38622

What it actually does

Integer overflow when allocating the len array in VZT facgeometry parsing leads to memory corruption that can be leveraged for arbitrary code execution.

Why it matters to the business

Attackers can gain full control of a user's workstation by tricking them into opening a malicious file, enabling data theft, ransomware deployment, or further network compromise.

How an attack unfolds

An attacker crafts a malicious .vzt file that triggers the integer overflow during facgeometry parsing. The victim opens the file in the affected GTKWave version, causing memory corruption that results in arbitrary code execution under the user's context.

How to fix it

Upgrade GTKWave to a patched release that corrects the integer overflow in VZT facgeometry parsing. Until a fix is released, restrict opening of untrusted .vzt files and run the application inside a sandbox or virtual machine.

How to confirm the fix worked

Confirm the installed GTKWave version is newer than the vulnerable release, then attempt to parse both benign and boundary-case .vzt files while monitoring for crashes or memory errors.

Typical attack path

1. Craft a .vzt file that triggers the integer overflow in facgeometry parsing
2. Deliver the file via email, download link, or shared storage
3. Social-engineer the victim into opening the file with GTKWave
4. Exploit the resulting memory corruption to execute attacker-controlled code

How to detect it

Review application crash logs and process creation events around GTKWave usage; look for unexpected child processes or memory allocation failures when .vzt files are processed.

What your security team should do

• Track upstream GTKWave releases and apply the fix immediately upon availability
• Block or quarantine .vzt files at email and web gateways until patches are deployed
• Configure endpoint protection to sandbox or restrict execution of waveform analysis tools