Adobe Substance 3D Stager: Out-of-bounds write allows code execution
Summary
Adobe Substance 3D Stager 3.1.8 and earlier on Windows and macOS contains an out-of-bounds write vulnerability (CWE-787). An attacker who convinces a user to open a malicious file can execute arbitrary code with the rights of the current user. No authentication is required, but user interaction is. Adobe reports no known exploitation in the wild.
Affected
- Adobe Substance 3D Stager 3.1.8 and earlier
- Windows and macOS
Fixed in
- Adobe Substance 3D Stager 3.1.9 (APSB26-170, published 13 October 2026)
Workaround
Unknown. No vendor-documented workaround for unpatched systems was found. Until the update is installed, open 3D or Stager files only from trusted sources.
Exploitation
- Adobe is not aware of any exploits in the wild.
- No public proof of concept was found.
- CISA SSVC assessment: exploitation none, automatable no, technical impact total.
Our recommendation
- Inventory Stager installations, including Steam installs, and confirm the version.
- Update to version 3.1.9 or later via Creative Cloud or Steam.
- Prioritise machines that handle external files and accounts with admin rights.
- Until patched, open 3D or Stager files only from trusted sources.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Adobe Security Bulletin APSB26-170 www.adobe.com
- Vulners: CVE-2026-103838 vulners.com
- Strix: CVE-2026-103838 www.strix.ai
- Vulners CVE list entry CVE-2026-103838 vulners.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 2 Nov 2026, 00:14.
Original description (NVD)
Substance3D - Stager is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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