PatchSiren cyber security CVE debrief
CVE-2026-21343 Adobe CVE debrief
Substance3D - Stager versions 3.1.6 and earlier are affected by an out-of-bounds read vulnerability when parsing a crafted file. This could result in a read past the end of an allocated memory structure, potentially allowing an attacker to execute code in the context of the current user if a victim opens a malicious file. The vulnerability requires user interaction and can be triggered by opening a specially crafted file. To mitigate this vulnerability, users should apply the vendor patch. This vulnerability has a high impact on confidentiality, integrity, and availability.
- Vendor
- Adobe
- Product
- Substance 3D Stager
- CVSS
- HIGH 7.8
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-02-10
- Original CVE updated
- 2026-08-28
- Advisory published
- 2026-02-10
- Advisory updated
- 2026-08-28
Who should care
Users of Substance3D - Stager versions 3.1.6 and earlier should apply the vendor patch to prevent potential code execution. This includes operators, platform administrators, vulnerability management teams, and security teams who need to assess and mitigate this vulnerability.
Technical summary
The vulnerability is caused by an out-of-bounds read when parsing a crafted file, which could result in a read past the end of an allocated memory structure. This could potentially allow an attacker to execute code in the context of the current user if a victim opens a malicious file. The vulnerability affects Substance3D - Stager versions 3.1.6 and earlier. It requires user interaction and can be triggered by opening a specially crafted file. The CVE Program and NVD provide official records and details on this vulnerability.
Defensive priority
High priority due to potential for code execution.
Recommended defensive actions
- Apply vendor patch
- Inventory vulnerable software
- Monitor for malicious files
- Review compensating controls for exposed systems while remediation is scheduled and verified
- Check relevant monitoring, detection, and logs for exposed assets that need extra review
- Track exceptions, retest remediated assets, and close the item only after evidence is documented
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
Evidence notes
The CVE record and NVD entry provide details on the vulnerability. Further analysis and verification are recommended. The vulnerability is caused by an out-of-bounds read when parsing a crafted file, which could result in a read past the end of an allocated memory structure. This could potentially allow an attacker to execute code in the context of the current user if a victim opens a malicious file. Users of Substance3D - Stager versions 3.1.6 and earlier should apply the vendor patch to prevent potential code execution. The CVE Program and NVD provide official records and details.
Sources and references
Verified primary and authoritative sources
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CVE-2026-21343 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-21343
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-21343 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-21343
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
-
Source reference
Unverified legacy reference
URL: https://helpx.adobe.com/security/products/substance3d_stager/apsb26-20.html
[email protected] - Vendor Advisory
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.