CVE-2026-10233 in Assimp
Summary
by MITRE • 06/01/2026
A security vulnerability has been detected in Assimp up to 6.0.4. Affected by this issue is the function HL1MDLLoader::read_sequence_infos of the file HL1MDLLoader.cpp of the component Half-Life 1 MDL Loader. The manipulation of the argument aiString leads to out-of-bounds read. The attack needs to be performed locally. The exploit has been disclosed publicly and may be used. The project tagged the reported issue as bug.
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Analysis
by VulDB Data Team • 06/07/2026
The security vulnerability in Assimp version 6.0.4 and earlier affects the Half-Life 1 MDL Loader component through a critical flaw in the HL1MDLLoader::read_sequence_infos function located in HL1MDLLoader.cpp. This vulnerability represents a classic out-of-bounds read condition that occurs when processing the aiString argument, creating a potential vector for malicious code execution within the application context. The flaw specifically manifests during the parsing of Half-Life 1 MDL model files, which are commonly used in gaming applications and legacy software systems that rely on Assimp for 3D model loading capabilities.
The technical nature of this vulnerability stems from insufficient bounds checking within the HL1MDLLoader::read_sequence_infos function, which processes sequence information from Half-Life 1 model files. When the aiString parameter contains malformed or excessively large data, the function fails to validate array boundaries before accessing memory locations, resulting in unauthorized memory reads beyond the allocated buffer space. This type of vulnerability falls under CWE-129, which specifically addresses insufficient validation of length of inputs, and represents a direct violation of secure coding practices that mandate proper input sanitization and boundary validation. The issue is particularly concerning as it exists within a file format loader that may be invoked by various applications, including game engines, 3D modeling tools, and legacy systems that have not been updated to address this specific flaw.
The operational impact of this vulnerability is significant despite requiring local execution for exploitation. The public disclosure of the exploit means that malicious actors can leverage this flaw to potentially extract sensitive information from memory, cause application crashes, or in more sophisticated scenarios, potentially escalate privileges within the local system. The vulnerability affects systems that process Half-Life 1 MDL files through Assimp's Half-Life 1 MDL Loader component, which could include gaming applications, legacy 3D model viewers, or any software that integrates Assimp for model format support. This creates a wide attack surface across various software ecosystems where Assimp is utilized, particularly in environments where users may encounter untrusted 3D model files. The local execution requirement does not diminish the threat level, as attackers can often achieve local access through social engineering, phishing attacks, or by compromising systems where users regularly interact with 3D content files.
Mitigation strategies for this vulnerability should focus on immediate remediation through software updates to Assimp version 6.0.5 or later, which contains the necessary patches to address the out-of-bounds read condition. Organizations should implement comprehensive vulnerability management procedures to ensure all systems utilizing Assimp are updated promptly, particularly in environments where untrusted 3D model files may be processed. Additional defensive measures include implementing strict input validation for all model file processing, utilizing memory protection mechanisms such as address space layout randomization and stack canaries, and employing runtime monitoring to detect anomalous memory access patterns. The vulnerability also highlights the importance of following ATT&CK framework principles for defensive measures, particularly focusing on privilege escalation and execution techniques that attackers might employ through such memory corruption vulnerabilities. Regular security assessments and code reviews should be conducted to identify similar patterns in other file format loaders within the software ecosystem, as this represents a common class of vulnerability that can affect various multimedia processing components.