CVE-2025-3549 is a heap-based buffer overflow vulnerability identified in version 5.4.3 of the Open Asset Import Library (Assimp), specifically within the function Assimp::MD3Importer::ValidateSurfaceHeaderOffsets located in the MD3Loader.cpp source file. Assimp is a widely used open-source library designed to import various 3D model formats into applications, commonly utilized in game development, CAD, and visualization software. The vulnerability arises from improper validation of surface header offsets when processing MD3 model files, which can lead to a heap-based buffer overflow condition. This overflow occurs when the function processes crafted input data that manipulates the offsets, causing memory corruption on the heap. Exploitation requires local access with at least low privileges (PR:L) and does not require user interaction (UI:N). The attack vector is local, meaning an attacker must have some form of access to the target system to trigger the vulnerability. The CVSS 4.0 base score is 4.8, indicating a medium severity level, reflecting limited impact due to the local attack vector and required privileges. No known exploits are currently reported in the wild, and no official patches have been linked yet. However, the vulnerability has been publicly disclosed, increasing the risk of future exploitation. The heap overflow could potentially be leveraged to execute arbitrary code, escalate privileges, or cause denial of service by crashing the application using Assimp to load malicious MD3 files. Given Assimp's role in processing 3D assets, software that integrates this library and processes untrusted or user-supplied 3D models is at risk. This includes game engines, 3D content creation tools, and visualization platforms that rely on Assimp 5.4.3 for MD3 file handling.

For European organizations, the impact of CVE-2025-3549 depends largely on their use of Assimp 5.4.3 within their software stack. Organizations involved in game development, 3D modeling, CAD, and simulation industries that process MD3 files could face risks of local privilege escalation or application crashes, potentially disrupting development workflows or production environments. While the vulnerability requires local access and low privileges, insider threats or compromised user accounts could exploit this flaw to escalate privileges or execute arbitrary code, leading to data breaches or system compromise. The medium CVSS score reflects limited remote exploitation potential; however, the risk remains significant in environments where users run untrusted 3D assets or where multiple users share systems. Critical infrastructure or defense contractors using Assimp for visualization or simulation may face operational disruptions or targeted attacks leveraging this vulnerability. Additionally, the lack of an official patch at the time of disclosure increases exposure. European organizations with strict data protection regulations (e.g., GDPR) must consider the risk of data integrity and availability impacts, especially if this vulnerability is exploited to disrupt services or corrupt data processing pipelines involving 3D assets.

To mitigate CVE-2025-3549, European organizations should: 1) Immediately audit their software environments to identify any use of Assimp version 5.4.3, particularly in applications processing MD3 files. 2) Restrict local access to systems running vulnerable software to trusted users only, minimizing the risk of local exploitation. 3) Implement strict input validation and sandboxing for any 3D model files loaded by applications using Assimp, ensuring untrusted files are not processed without proper isolation. 4) Monitor for unusual application crashes or behavior in software utilizing Assimp, as these may indicate exploitation attempts. 5) Engage with software vendors or open-source maintainers to obtain patches or upgrade to a fixed version once available; if no patch exists, consider temporarily disabling MD3 file support or replacing Assimp with alternative libraries. 6) Employ endpoint detection and response (EDR) tools to detect potential local privilege escalation or heap overflow exploitation techniques. 7) Educate developers and system administrators about the risks of processing untrusted 3D assets and enforce the principle of least privilege on affected systems. These targeted actions go beyond generic advice by focusing on controlling local access, input validation, and proactive monitoring specific to the vulnerability context.