CVE-2026-21302 is classified as an out-of-bounds read vulnerability (CWE-125) affecting Adobe Substance3D - Modeler, a 3D modeling software widely used in digital content creation. The vulnerability exists in versions 1.22.4 and earlier, where the software improperly handles memory boundaries when processing certain input files. An attacker can craft a malicious file that, when opened by a victim, causes the application to read memory outside the intended buffer limits. This can lead to exposure of sensitive information residing in adjacent memory areas, such as user data, application secrets, or other confidential information. The vulnerability requires user interaction—specifically, the victim must open the malicious file—and does not require any privileges or authentication. The CVSS v3.1 base score is 5.5, reflecting a medium severity level, with the vector indicating local attack vector (AV:L), low attack complexity (AC:L), no privileges required (PR:N), user interaction required (UI:R), unchanged scope (S:U), high confidentiality impact (C:H), no integrity impact (I:N), and no availability impact (A:N). Currently, there are no known exploits in the wild, and Adobe has not yet published patches. The vulnerability primarily threatens confidentiality by exposing memory contents but does not affect integrity or availability. This flaw is particularly relevant for organizations that handle sensitive or proprietary 3D design data, as memory exposure could lead to leakage of intellectual property or personal data.

For European organizations, the primary impact of CVE-2026-21302 is the potential leakage of sensitive information through memory exposure. Companies involved in digital content creation, media production, gaming, architecture, and industrial design that utilize Adobe Substance3D - Modeler could inadvertently expose proprietary designs, client data, or confidential project details. Although the vulnerability does not allow code execution or system compromise, the confidentiality breach could lead to intellectual property theft or competitive disadvantage. The requirement for user interaction means that social engineering or phishing tactics could be used to deliver malicious files, increasing the risk in environments where file sharing is common. The impact is more pronounced in sectors with strict data protection regulations such as GDPR, where unauthorized disclosure of personal or sensitive data can result in regulatory penalties and reputational damage. Additionally, the lack of a patch at the time of disclosure means organizations must rely on interim mitigations, increasing exposure duration.

European organizations should implement the following specific mitigations: 1) Educate users to be cautious when opening files from untrusted or unknown sources, especially those related to 3D modeling projects. 2) Establish strict file validation and scanning procedures for incoming files using advanced endpoint protection solutions capable of detecting malformed or suspicious 3D model files. 3) Limit the use of Adobe Substance3D - Modeler to trusted environments and consider sandboxing or isolating the application to contain potential memory exposure risks. 4) Monitor for unusual file access patterns or user behavior that could indicate exploitation attempts. 5) Maintain an inventory of all software versions in use and prioritize upgrading to patched versions once Adobe releases updates addressing this vulnerability. 6) Collaborate with Adobe support and subscribe to security advisories to receive timely notifications. 7) Implement network segmentation to reduce the risk of lateral movement if an attacker gains initial access through this vector. 8) Consider deploying Data Loss Prevention (DLP) tools to detect and prevent unauthorized exfiltration of sensitive data that might be exposed due to this vulnerability.