CVE-2020-7489 in EcoStruxure Machine Expert
Summary
by MITRE
A CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') vulnerability exists on EcoStruxure Machine Expert – Basic or SoMachine Basic programming software (versions in security notification). The result of this vulnerability, DLL substitution, could allow the transference of malicious code to the controller.
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Analysis
by VulDB Data Team • 05/29/2026
The CVE-2020-7489 vulnerability represents a critical injection flaw within Schneider Electric's EcoStruxure Machine Expert and SoMachine Basic programming software environments. This vulnerability manifests as an improper neutralization of special elements in output used by downstream components, directly mapping to CWE-74 classification. The flaw exists within the software's handling of dynamic link library (DLL) loading processes, creating an exploitable condition where malicious code can be transferred to industrial controllers through DLL substitution techniques.
The technical implementation of this vulnerability stems from insufficient validation of dynamic library loading mechanisms within the programming software environment. When users open projects or execute certain operations, the software may load DLL files from predictable or user-controllable locations without proper integrity checks or path validation. This creates a pathway for attackers to replace legitimate DLL files with malicious counterparts, effectively enabling code execution within the context of the running programming environment. The vulnerability is particularly concerning in industrial control systems where these programming tools are used to configure and deploy controller software.
The operational impact of this vulnerability extends beyond simple code execution, as it represents a sophisticated attack vector targeting industrial automation environments. Attackers can leverage this flaw to gain unauthorized access to controller configurations, potentially leading to system compromise, operational disruption, or even physical security breaches in industrial settings. The vulnerability's exploitation can result in persistent backdoors, data exfiltration, or manipulation of critical industrial processes. This aligns with ATT&CK technique T1059.001 for command and scripting interpreter and T1547.001 for registry run keys, as malicious DLLs can establish persistence mechanisms within the software environment.
Mitigation strategies for CVE-2020-7489 require comprehensive system hardening approaches that address both the immediate vulnerability and broader security posture. Organizations should implement strict file system permissions, disable unnecessary DLL loading capabilities, and establish robust software integrity verification mechanisms. The implementation of application whitelisting solutions can prevent unauthorized DLL execution, while regular security updates and patches should be prioritized to address the root cause. Network segmentation and monitoring solutions should be deployed to detect anomalous DLL loading activities. Additionally, security awareness training for industrial control system operators is crucial to prevent social engineering attacks that might exploit this vulnerability through compromised user credentials or insider threats. The vulnerability highlights the importance of secure coding practices and proper input validation as outlined in OWASP Top 10 2021 category A03: Data Exposure and A06: Security Misconfiguration.