# CVE-2026-21340: Adobe Substance3D Designer out-of-bounds read in file parsing

Source: https://junglewise.ai/threats/cve-2026-21340-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-2026-21340 · Severity: medium · CVSS 5.5 · Published 2026-02-10

Substance3D Designer is Adobe's professional 3D design tool used by creative professionals to create and manipulate 3D assets. A memory exposure flaw in file parsing could allow attackers to leak sensitive data from the application's memory if a user opens a specially crafted malicious file. This could result in the exposure of design data, credentials, or other confidential information stored in memory during the design session.

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-2026-21340 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-21340 being exploited in the wild.

**How severe is CVE-2026-21340?** 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-2026-21340?** 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-2026-21340 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-21340?** 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 flaw in Substance3D Designer's file parsing logic affecting versions 15.1.0 and earlier. An attacker can craft a malicious design file that, when opened by a victim, triggers an out-of-bounds memory read, allowing the attacker to access and exfiltrate arbitrary data from the application's memory. The attack vector requires user interaction (opening the malicious file), but no authentication or elevated privileges are needed. An attacker could leverage this to disclose sensitive information including design files, credentials, or other confidential data residing in memory. Adobe has addressed this in a security update; patches should be applied to versions later than 15.1.0.

## 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)