# CVE-2026-21339: Adobe Substance3D Designer out-of-bounds read in file parsing

Source: https://junglewise.ai/threats/cve-2026-21339-adobe-substance3d-designer-out-of-bounds-read-in-file-parsing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-02-10. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-21339 · Severity: medium · CVSS 5.5 · Published 2026-02-10

Substance3D Designer is a professional 3D content creation tool used by designers and artists. Versions 15.1.0 and earlier contain a memory read vulnerability that could expose sensitive data when a user opens a malicious file. An attacker could exploit this to steal design data, credentials, or other confidential information stored in memory.

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

## Quick answers

**Is CVE-2026-21339 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-21339 being exploited in the wild.

**How severe is CVE-2026-21339?** Medium severity, with a CVSS score of 5.5, published 10 February 2026.

**Which products and versions are affected?** Adobe Substance3D Designer 15.1.0 and earlier.

**Is there a fix for CVE-2026-21339?** 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-2026-21339 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-21339?** Check whether you run Adobe Substance 3d Designer or Adobe Substance3D Designer 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 read that occurs during file parsing in Substance3D Designer versions 15.1.0 and earlier. The root cause appears to be improper bounds checking when reading from memory during file processing. Exploitation requires user interaction—specifically, a victim must open a specially crafted malicious file. The attack vector is local (user must interact with the application). Successful exploitation allows an attacker to read arbitrary memory content, potentially disclosing sensitive information such as design files, API keys, or other confidential data held in the application's memory. Adobe has issued a security advisory addressing this issue.

## Affected products

- Adobe Substance3D Designer 15.1.0 and earlier

## Timeline

- 2026-02-10: disclosed

## References

- [https://helpx.adobe.com/security/products/substance3d_designer/apsb26-19.html](https://helpx.adobe.com/security/products/substance3d_designer/apsb26-19.html)

## Related threats

- [Adobe Substance 3D Designer NULL pointer dereference denial-of-service](https://junglewise.ai/threats/cve-2026-103829-substance3d-designer-is-affected-by-a-null-pointer-dereference)
- [Adobe Substance 3D Designer null pointer dereference](https://junglewise.ai/threats/cve-2026-103828-substance3d-designer-is-affected-by-a-null-pointer-dereference)
- [Adobe Substance 3D Designer stack-based buffer overflow](https://junglewise.ai/threats/cve-2026-103827-substance3d-designer-is-affected-by-a-stack-based-buffer)
- [Adobe Substance 3D Designer null pointer dereference](https://junglewise.ai/threats/cve-2026-103826-substance3d-designer-is-affected-by-a-null-pointer-dereference)
- [Adobe Substance 3D Designer out-of-bounds read in file parsing](https://junglewise.ai/threats/cve-2026-103825-substance3d-designer-is-affected-by-an-out-of-bounds-read)