CVE-2023-35951

What it actually does

Stack-based buffer overflow in OFF file vertex parsing allows an attacker-supplied file to overwrite memory and execute arbitrary code.

Why it matters to the business

Attackers can gain full control of affected systems by tricking users into opening a malicious geometry file, leading to data theft, service disruption, and potential ransomware deployment; the vulnerability affects widely used open-source components with high downstream prevalence.

How an attack unfolds

An attacker creates a specially crafted .off file that overflows a stack buffer during vertex parsing. The file is delivered to a victim who opens it with software that uses the vulnerable parsing code, resulting in arbitrary code execution on the victim's machine.

How to fix it

Update zitadel/zitadel to one of the fixed commits: 22e2d5599918864877e054ebe82fb834a5aa1077 or 393f711ca7f94dbd7805fd99df2a0eea58fd7aaf. Rebuild and redeploy any dependent applications. Disable processing of untrusted .off files until patches are applied.

How to confirm the fix worked

Verify the running binary or library no longer contains the vulnerable readOFF.cpp code path by inspecting the commit hash or performing a rebuild from a patched source tree. Test with a benign .off file to confirm normal operation and with a crafted overflow test case to confirm the crash is prevented.

Typical attack path

1. Craft a malicious .off file that triggers the buffer overflow in readOFF.cpp vertex parsing
2. Deliver the file to the target via email, download link, or shared storage
3. Victim opens the file using an application linked against the vulnerable library version
4. Overflow executes attacker-controlled code with the privileges of the victim process

How to detect it

Review file-access logs and process creation events for unexpected execution of applications that consume .off files. Look for crashes or memory-corruption signals in processes handling geometry input shortly after a suspicious file was accessed.

What your security team should do

• Immediately upgrade all zitadel/zitadel instances to the listed fixed commits
• Add .off file handling to the list of untrusted input formats requiring sandboxing or blocking
• Scan internal repositories and build pipelines for any direct or transitive dependency on libigl 2.4.0
• Monitor vulnerability disclosure feeds for related issues in geometry parsing libraries