# CVE-2026-10229: Assimp heap overflow in HL1MDLLoader

Source: https://junglewise.ai/threats/cve-2026-10229-assimp-heap-overflow-in-hl1mdlloader  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-01. Updated: 2026-06-01  
License: CC BY 4.0 with a link back

CVE-2026-10229 · Severity: medium · CVSS 5.3 · Published 2026-06-01

Assimp, a library used to import 3D models into various applications, contains a vulnerability in its Half-Life 1 model loader. An attacker can provide a specially crafted 3D model file that, when processed, causes the application to crash or potentially execute unauthorized code. This could lead to a loss of system stability or unauthorized access to data on the local machine.

Technologies: [Assimp](https://junglewise.ai/threats/technologies/assimp). Vendors: [Assimp](https://junglewise.ai/threats/vendors/assimp).

## Quick answers

**Is CVE-2026-10229 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-10229 being exploited in the wild.

**How severe is CVE-2026-10229?** Medium severity, with a CVSS score of 5.3, published 1 June 2026.

**Which products and versions are affected?** Assimp up to 6.0.4.

**Is there a fix for CVE-2026-10229?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-10229 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-10229?** Check whether you run Assimp at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A heap-based buffer overflow exists in Assimp up to version 6.0.4 within the HL1MDLLoader::read_meshes function in HL1MDLLoader.cpp. The vulnerability is triggered when parsing a malformed Half-Life 1 MDL file where vertex data references a bone index that exceeds the number of bones declared in the file header (e.g., referencing index 5 when only 1 bone is defined). This results in an out-of-bounds read/write on the temp_bones_ vector. An attacker with local access can exploit this by providing a malicious MDL file to an application using the library, potentially achieving arbitrary code execution or a denial-of-service. A public proof-of-concept (PoC) has been disclosed.

## Affected products

- Assimp Assimp up to 6.0.4

## Timeline

- 2026-06-01: disclosed: Vulnerability disclosed and CVE assigned.
- 2026-06-01: advisory: NVD and VulDB published advisories.

## References

- [https://github.com/assimp/assimp/](https://github.com/assimp/assimp/)
- [https://github.com/assimp/assimp/issues/6614](https://github.com/assimp/assimp/issues/6614)
- [https://github.com/user-attachments/files/27194364/poc.zip](https://github.com/user-attachments/files/27194364/poc.zip)
- [https://vuldb.com/cve/CVE-2026-10229](https://vuldb.com/cve/CVE-2026-10229)
- [https://vuldb.com/submit/821189](https://vuldb.com/submit/821189)
- [https://vuldb.com/vuln/367508](https://vuldb.com/vuln/367508)
- [https://vuldb.com/vuln/367508/cti](https://vuldb.com/vuln/367508/cti)

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