CVE-2023-39272

What it actually does

Integer overflow when allocating the lsb array during LXT2 facgeometry parsing leads to memory corruption that can be leveraged for arbitrary code execution.

Why it matters to the business

Attackers can fully compromise user workstations running GTKWave by delivering a malicious waveform file, enabling data theft, persistence, or further network access with no patch currently published.

How an attack unfolds

An attacker crafts a .lxt2 file that triggers the integer overflow in facgeometry parsing. The victim opens the file in GTKWave, the overflow corrupts memory structures, and attacker-controlled data is written into executable regions to achieve code execution.

How to fix it

Upgrade to a patched release of GTKWave once available; until then restrict opening of untrusted .lxt2 files and run the application under sandboxing or least-privilege constraints.

How to confirm the fix worked

Confirm GTKWave version and test file handling behavior against known proof-of-concept .lxt2 samples; monitor vendor advisories for fixed builds.

Typical attack path

1. Craft .lxt2 file containing malformed facgeometry data to induce lsb array integer overflow
2. Deliver file to target via email, download link, or shared storage
3. Victim opens file in vulnerable GTKWave instance
4. Overflow during allocation allows memory corruption and subsequent arbitrary code execution

How to detect it

Review endpoint logs and EDR telemetry for GTKWave process crashes, unexpected memory allocations, or child process creation immediately after .lxt2 file access.

What your security team should do

• Block or sandbox GTKWave execution on untrusted .lxt2 files until a patch is released
• Add file-type filtering and user education to reduce accidental opening of malicious waveform files
• Hunt for GTKWave crashes or anomalous child processes in endpoint telemetry