CVE-2025-21166 in Substance3D
Summary
by MITRE • 07/08/2025
Substance3D - Designer versions 14.1 and earlier are 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.
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Analysis
by VulDB Data Team • 07/08/2025
The vulnerability identified as CVE-2025-21166 affects Substance3D Designer versions 14.1 and earlier, representing a critical out-of-bounds write flaw that could enable arbitrary code execution when a victim opens a malicious file. This vulnerability resides within the file parsing functionality of the software, specifically when processing specially crafted input files that trigger memory corruption conditions. The issue manifests as an improper bounds check during the handling of file data structures, allowing an attacker to write data beyond the allocated memory boundaries. The vulnerability is classified under CWE-787 Out-of-bounds Write, which is a well-documented weakness in software security that occurs when a program writes data past the end of a buffer or array, potentially overwriting adjacent memory locations. The attack requires user interaction through social engineering or phishing techniques to convince victims to open malicious files, making it a client-side exploitation vector that leverages user trust and behavior patterns.
The technical exploitation of this vulnerability occurs when Substance3D Designer processes a malformed file that contains crafted data structures designed to trigger the buffer overflow condition. During normal operation, the application parses file headers and data sections to reconstruct the visual elements and materials within the design environment. However, when encountering malicious input, the parsing routine fails to validate array indices or buffer sizes properly, leading to memory corruption that can be leveraged to execute arbitrary code with the privileges of the currently logged-in user. This type of vulnerability falls under the ATT&CK technique T1203 Exploitation for Client Execution, where adversaries leverage software vulnerabilities to execute malicious code on target systems. The memory corruption typically results in a crash or more dangerously, allows an attacker to inject and execute shellcode in the application's memory space, potentially leading to complete system compromise.
The operational impact of this vulnerability extends beyond immediate code execution capabilities, as it represents a significant risk to users who regularly work with design files and may encounter malicious content through various attack vectors. Attackers can craft specially designed .sbsar or .sbs file formats that, when opened in the vulnerable software, trigger the out-of-bounds write condition. The vulnerability affects all users running Substance3D Designer versions 14.1 and earlier, making it particularly concerning given the widespread adoption of this design software in creative workflows. Organizations that rely on Substance3D for material creation and design work face potential exposure to supply chain attacks, where legitimate files are compromised or malicious files are distributed through trusted channels. The attack surface is particularly broad since the vulnerability can be triggered through any file format that the software processes, including project files, material libraries, or template files that may be shared across teams or downloaded from third-party sources.
Mitigation strategies for CVE-2025-21166 should focus on immediate software updates and operational security measures to reduce the attack surface. The primary remediation involves upgrading to Substance3D Designer version 14.2 or later, which includes patches that address the buffer overflow condition through proper bounds checking and input validation. Organizations should implement strict file validation policies and consider sandboxing environments for handling untrusted files, as recommended in the NIST Cybersecurity Framework. Network-based mitigations could include implementing file type restrictions and content filtering to prevent malicious files from reaching users, while endpoint protection solutions should be configured to monitor for suspicious file access patterns. The vulnerability also underscores the importance of user education and awareness training to recognize potential social engineering attempts that might lead to exploitation. Security teams should conduct vulnerability assessments to identify all instances of the vulnerable software within their environments and establish monitoring procedures to detect potential exploitation attempts. Additionally, implementing principle of least privilege controls and regular security updates for all design and creative software applications helps reduce overall risk exposure. The ATT&CK framework suggests implementing defensive measures such as application whitelisting and runtime application control to prevent unauthorized code execution, which would provide additional protection against exploitation of this and similar vulnerabilities.