CVE-2021-31342 in Solid Edge
Summary
by MITRE • 06/09/2021
The ugeom2d.dll library in all versions of Solid Edge SE2020 before 2020MP14 and all versions of Solid Edge SE2021 before SE2021MP5 lack proper validation of user-supplied data when parsing DFT files. This could result in an out-of-bounds write past the end of an allocated structure. An attacker could leverage this vulnerability to execute code in the context of the current process.
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Analysis
by VulDB Data Team • 06/11/2021
The vulnerability identified as CVE-2021-31342 resides within the ugeom2d.dll library component of Siemens Solid Edge software versions prior to specific maintenance releases. This issue affects both Solid Edge SE2020 before 2020MP14 and Solid Edge SE2021 before SE2021MP5, representing a critical security flaw that impacts the software's ability to safely process DFT (Drafting File Format) files. The root cause stems from insufficient input validation mechanisms within the library's parsing routine for these specific file formats, creating a pathway for malicious code execution through memory corruption.
The technical flaw manifests as an out-of-bounds write condition that occurs when the ugeom2d.dll library processes user-supplied DFT files without adequate bounds checking. This vulnerability classifies under CWE-787: Out-of-bounds Write, which is a direct consequence of improper input validation and memory management practices. When the library encounters malformed or specially crafted DFT files, it fails to validate the size or structure of incoming data before attempting to write to allocated memory regions, resulting in memory corruption that can be exploited to overwrite adjacent memory locations.
The operational impact of this vulnerability extends beyond simple memory corruption, as it provides attackers with the capability to execute arbitrary code within the context of the currently running Solid Edge process. This privilege escalation scenario presents significant risks to organizations relying on Solid Edge for engineering and design work, as successful exploitation could lead to complete system compromise. Attackers could leverage this vulnerability through social engineering tactics, delivering malicious DFT files via email attachments, file sharing platforms, or compromised websites, making the attack vector particularly insidious given the widespread use of CAD software in enterprise environments.
Security professionals should consider this vulnerability in the context of the ATT&CK framework, specifically under the T1059.001 technique for Command and Scripting Interpreter, as exploitation could enable attackers to execute malicious code with the privileges of the Solid Edge application. The vulnerability's exploitation requires minimal user interaction beyond opening a malicious file, making it particularly dangerous in enterprise settings where design files are frequently shared between teams. Organizations should prioritize patching this vulnerability through the official Solid Edge maintenance releases, as the affected software versions represent a significant attack surface that could be leveraged for persistent threats.
Mitigation strategies should include immediate deployment of the vendor-provided patches for Solid Edge SE2020MP14 and SE2021MP5, along with network-based restrictions that prevent unauthorized file transfers containing potentially malicious DFT files. Additionally, organizations should implement robust file validation procedures and consider sandboxing mechanisms for processing untrusted design files. The vulnerability demonstrates the critical importance of input validation in software security, particularly for applications handling complex file formats that are frequently exchanged between users in collaborative engineering environments.