CVE-2021-41578 in myDESIGNER
Summary
by MITRE • 10/04/2021
mySCADA myDESIGNER 8.20.0 and below allows Directory Traversal attacks when importing project files. If an attacker can trick a victim into importing a malicious mep file, then they gain the ability to write arbitrary files to OS locations where the user has permission. This would typically lead to code execution.
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Analysis
by VulDB Data Team • 10/08/2021
The vulnerability identified as CVE-2021-41578 affects mySCADA myDESIGNER software versions 8.20.0 and earlier, presenting a critical directory traversal flaw that enables remote code execution through malicious project file imports. This vulnerability resides in the software's project file handling mechanism, specifically during the import process of .mep files which are used to store project configurations and design elements within the mySCADA ecosystem. The flaw allows attackers to manipulate file paths during import operations, bypassing normal file system access controls and potentially writing arbitrary files to locations within the operating system where the application has execution permissions.
The technical implementation of this vulnerability stems from inadequate input validation and path sanitization within the myDESIGNER application's file import functionality. When processing maliciously crafted .mep files, the software fails to properly validate or sanitize file paths contained within the project data structure, allowing attackers to specify absolute or relative paths that traverse outside the intended project directory boundaries. This weakness aligns with CWE-22 Directory Traversal vulnerability classification, which specifically addresses improper restriction of pathname characters or components that allows attackers to access files or directories outside the intended scope. The vulnerability is particularly dangerous because it operates at the file system level, where the application's privileges determine what files can be written or modified.
The operational impact of this vulnerability extends beyond simple file manipulation to encompass complete system compromise when exploited successfully. An attacker who can convince a legitimate user to import a malicious .mep file can potentially write malware directly to system directories, install backdoors, or modify existing executables to achieve persistent access. This attack vector is particularly concerning in industrial control environments where mySCADA software is commonly deployed, as it could enable attackers to disrupt critical infrastructure operations or gain unauthorized access to sensitive operational data. The vulnerability creates a pathway for attackers to escalate privileges through the application's existing user permissions, making it a significant concern for organizations operating in regulated industries where security compliance is paramount.
Mitigation strategies for CVE-2021-41578 should prioritize immediate software updates to versions that address the directory traversal vulnerability, as this represents the most effective defense against exploitation. Organizations should implement strict file validation policies that prevent the import of untrusted project files and establish network segmentation to limit access to myDESIGNER applications. Security controls should include mandatory file signature verification, implementation of least privilege principles for application execution, and regular security assessments of industrial control systems. Additionally, network monitoring should be enhanced to detect suspicious file transfer activities and unauthorized import operations. From an ATT&CK framework perspective, this vulnerability maps to techniques involving T1059 Command and Scripting Interpreter and T1078 Valid Accounts, as attackers can leverage legitimate user accounts to execute malicious code through the vulnerable import functionality. Organizations should also consider implementing application whitelisting solutions and mandatory access controls to prevent unauthorized file operations that could lead to system compromise.