CVE-2021-46151 in Simcenter Femap
Summary
by MITRE • 02/09/2022
A vulnerability has been identified in Simcenter Femap V2020.2 (All versions), Simcenter Femap V2021.1 (All versions). Affected application contains an out of bounds write past the end of an allocated structure while parsing specially crafted NEU files. This could allow an attacker to execute code in the context of the current process. (ZDI-CAN-14754, ZDI-CAN-15082)
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 02/12/2022
This vulnerability exists in Siemens Simcenter Femap software versions 2020.2 and 2021.1, representing a critical out-of-bounds write condition that occurs during the parsing of specially crafted NEU files. The flaw manifests when the application processes malformed input data, specifically within the memory management routines that handle finite element model data structures. The vulnerability is classified as a buffer overflow condition that allows attackers to write data beyond the allocated memory boundaries of a structure, creating a potential code execution vector. This type of vulnerability falls under CWE-787: "Out-of-bounds Write" and represents a fundamental memory safety issue that can be exploited to gain arbitrary code execution within the application's process context.
The technical exploitation of this vulnerability requires an attacker to craft a malicious NEU file that triggers the specific parsing logic where the out-of-bounds write occurs. When the vulnerable application loads this crafted file, the memory corruption results in the overwrite of adjacent memory locations, potentially allowing an attacker to manipulate program execution flow. The attack vector is typically through social engineering or file attachment scenarios where users open the malicious NEU file, making this a significant risk for engineering and simulation environments where such files are commonly exchanged. The vulnerability is particularly dangerous because it operates within the application's legitimate parsing routines, making detection more challenging and allowing the attack to appear as normal application behavior.
The operational impact of this vulnerability extends beyond simple code execution, as it can lead to complete system compromise when attackers leverage this flaw in enterprise environments. Engineering teams using Simcenter Femap in critical design and simulation workflows face potential data loss, system infiltration, and unauthorized access to sensitive design information. The vulnerability affects users who may not have administrative privileges, as the code execution occurs within the context of the running application process, potentially allowing attackers to escalate privileges or access additional system resources. This makes the vulnerability particularly concerning for organizations that rely heavily on finite element analysis and simulation software, where the integrity of design data is paramount.
Mitigation strategies for this vulnerability should include immediate patching of affected software versions, as Siemens has released updates to address the out-of-bounds write condition. Organizations should implement strict file validation procedures for NEU files received from external sources, including sandboxing or virtualized environments for file analysis. Network segmentation and access controls can help limit the potential impact if exploitation occurs, while regular security awareness training should emphasize the dangers of opening untrusted simulation files. The vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter and T1203 for Exploitation for Client Execution, making it a prime candidate for defensive measures focused on file validation and process monitoring. Additionally, organizations should conduct thorough security assessments of their simulation environments and implement automated tools to detect and prevent the execution of potentially malicious NEU files.