# CVE-2026-21305: Adobe Substance3D Painter out-of-bounds write

Source: https://junglewise.ai/threats/cve-2026-21305-adobe-substance3d-painter-out-of-bounds-write  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-01-13. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-21305 · Severity: high · CVSS 7.8 · Published 2026-01-13

Substance3D Painter is a digital painting and texturing tool used by 3D artists and game developers. Versions 11.0.3 and earlier contain a vulnerability that could allow an attacker to run malicious code on a user's computer if they open a specially crafted file. The attack requires the victim to manually open a malicious file, but successful exploitation could lead to complete system compromise.

Technologies: [Adobe Substance 3d Painter](https://junglewise.ai/threats/technologies/substance-3d-painter), [Adobe Substance3D Painter](https://junglewise.ai/threats/technologies/substance3d-painter). Vendors: [Adobe](https://junglewise.ai/threats/vendors/adobe).

## Quick answers

**Is CVE-2026-21305 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-21305 being exploited in the wild.

**How severe is CVE-2026-21305?** High severity, with a CVSS score of 7.8, published 13 January 2026.

**Which products and versions are affected?** Adobe Substance3D Painter 11.0.3 and earlier.

**Is there a fix for CVE-2026-21305?** 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-2026-21305 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-21305?** Check whether you run Adobe Substance 3d Painter or Adobe Substance3D Painter 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

The vulnerability is an out-of-bounds write flaw in Substance3D Painter versions 11.0.3 and earlier. The root cause involves improper bounds checking when processing input files, allowing an attacker to write data beyond allocated memory. The attack vector is local and requires user interaction—specifically, a victim must open a malicious file in the application. Successful exploitation can lead to arbitrary code execution in the context of the current user. There is no indication of active exploitation in the wild as of the advisory date. A patch is expected from Adobe via security bulletin APSB26-10.

## Affected products

- Adobe Substance3D Painter 11.0.3 and earlier

## Timeline

- 2026-01-13: disclosed

## References

- [https://helpx.adobe.com/security/products/substance3d_painter/apsb26-10.html](https://helpx.adobe.com/security/products/substance3d_painter/apsb26-10.html)

## Related threats

- [Adobe Substance 3D Painter out-of-bounds read in file parsing](https://junglewise.ai/threats/cve-2026-48380-substance3d-painter-is-affected-by-an-out-of-bounds-read)
- [Adobe Substance 3D Painter stack-based buffer overflow](https://junglewise.ai/threats/cve-2026-48379-substance3d-painter-is-affected-by-a-stack-based-buffer-overflow)
- [Adobe Substance3D Sampler heap buffer overflow](https://junglewise.ai/threats/cve-2026-34674-adobe-substance3d-sampler-heap-buffer-overflow)
- [Adobe Substance3D Painter out-of-bounds write](https://junglewise.ai/threats/cve-2026-75770-adobe-substance3d-painter-out-of-bounds-write)
- [Adobe Substance 3D Painter heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-75769-adobe-substance-3d-painter-heap-based-buffer-overflow)