CVE Alert: CVE-2025-54243 – Adobe – Substance3D – Viewer

**Risk verdict** High risk; arbitrary code execution in the current user context is possible if a user opens a crafted Substance3D – Viewer file, with exploitation requiring user interaction.

**Why this matters** For design teams, Substance3D assets are frequently shared and opened by end users; a successful exploit could compromise the attacker’s foothold on a workstation, exfiltrate assets, or facilitate further credential theft and lateral movement within the organisation. The impact is amplified where users hold elevated rights or have access to networked resources.

**Most likely attack path** Local attacker access is required and the user must interact (open a malicious file). An adversary would deliver a poisoned Substance3D file, the user opens it, and the viewer executes code with the user’s privileges. The flaw has high potential impact on confidentiality, integrity and availability, but scope remains unchanged unless additional privileges are acquired during exploitation.

**Who is most exposed** Organisations employing designers and engineers using Substance3D Viewer on Windows (and commonly macOS) workstations, especially where files are shared via email or cloud storage and opened without strict sandboxing or application whitelisting.

**Detection ideas**

• Crashes or crash dumps in Substance3D Viewer immediately after opening a file.
• Unusual memory or process activity associated with the viewer following a file open event.
• Security alerts for out-of-bounds write-related crashes or anomalous writes in the affected process.
• Unexpected file-open events from trusted collaboration channels that precede failures in the viewer.
• EDR detections of unusual privilege usage or persistence attempts linked to the viewer process.

**Mitigation and prioritisation**

• Patch to the latest Substance3D Viewer version addressing the affected range; confirm patch deployment in staging before production.
• Implement application whitelisting and sandboxing; restrict the viewer to a controlled execution environment.
• Enforce least privilege for end users; disable auto-execution of downloaded or external files; require user confirmation for file opens from untrusted sources.
• Enhance monitoring: instrument for viewer crashes tied to file opens; alert on memory-related anomalies in the viewer process.
• Change-management: communicate security update timing to design teams; run awareness training on phishing/file-sharing risks. If KEV is true or EPSS ≥ 0.5, treat as priority 1. Data permitting, confirm KEV/EPSS status to refine prioritisation.