CVE-2021-40155 in Navisworks
Summary
by MITRE • 09/16/2021
A maliciously crafted DWG file in Autodesk Navisworks 2019, 2020, 2021, 2022 can be forced to read beyond allocated boundaries when parsing the DWG files. This vulnerability can be exploited to execute arbitrary code.
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Analysis
by VulDB Data Team • 09/19/2021
The vulnerability identified as CVE-2021-40155 represents a critical buffer overflow condition within Autodesk Navisworks software versions 2019 through 2022. This flaw manifests when the application processes maliciously crafted DWG files, which are industry-standard computer-aided design files used extensively in construction and engineering projects. The vulnerability stems from insufficient input validation during the parsing of DWG file structures, specifically when handling boundary conditions within the file's internal data representation.
The technical implementation of this vulnerability falls under CWE-129, which describes improper validation of array index values, and CWE-787, which covers out-of-bounds write operations. When Autodesk Navisworks attempts to parse a malformed DWG file, the software fails to properly validate the size and boundaries of data structures before accessing memory locations. This allows an attacker to craft a specially designed DWG file that, when opened by the vulnerable software, causes the application to read beyond its allocated memory boundaries, leading to memory corruption and potential code execution.
From an operational perspective, this vulnerability poses significant risk to organizations utilizing Autodesk Navisworks for project collaboration and design review processes. The attack vector typically involves social engineering techniques where an attacker delivers a malicious DWG file through email attachments, shared network drives, or collaboration platforms commonly used in construction and engineering workflows. Once opened by an unsuspecting user, the malicious file can trigger arbitrary code execution on the victim's system, potentially allowing attackers to establish persistent access, escalate privileges, or deploy additional malware.
The impact of this vulnerability extends beyond simple code execution as it can be leveraged for privilege escalation and lateral movement within network environments. According to ATT&CK framework, this vulnerability maps to T1059.007 for command and scripting interpreter and T1068 for local privilege escalation. Organizations running these legacy versions of Navisworks face heightened risk since the software is often used in enterprise environments where users may not be security-aware and where multiple stakeholders frequently exchange design files. The vulnerability's exploitation requires no special privileges for initial compromise, making it particularly dangerous in collaborative environments where file sharing is routine.
Effective mitigation strategies for CVE-2021-40155 include immediate deployment of Autodesk's official security patches and updates for Navisworks 2019 through 2022. Organizations should implement strict file validation policies and consider deploying sandboxed environments for opening potentially malicious files. Network segmentation and access controls can help limit the potential impact if exploitation occurs. Additionally, security awareness training for users handling design files, along with regular vulnerability assessments of CAD software environments, should be implemented to reduce the attack surface and prevent successful exploitation attempts.