CVE-2021-36031 in Magento Commerce
Summary
by MITRE • 09/01/2021
Magento Commerce versions 2.4.2 (and earlier), 2.4.2-p1 (and earlier) and 2.3.7 (and earlier) are affected by a Path Traversal vulnerability via the `theme[preview_image]` parameter. An attacker with admin privileges could leverage this vulnerability to achieve remote code execution.
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Analysis
by VulDB Data Team • 09/04/2021
This vulnerability exists within Magento Commerce platforms where the `theme[preview_image]` parameter fails to properly validate file paths during theme preview operations. The flaw allows for directory traversal attacks that can be exploited by authenticated administrators to access arbitrary files on the server. The vulnerability stems from insufficient input sanitization and path validation mechanisms that permit attackers to manipulate file system access through crafted parameters. According to CWE-22, this represents a classic path traversal weakness where user-supplied input is directly incorporated into file system operations without proper validation. The attack vector requires administrative privileges, making it particularly dangerous as it can be leveraged for privilege escalation and persistent access to the compromised system.
The technical implementation of this vulnerability allows an attacker to manipulate the theme preview functionality to traverse directories and access files outside the intended theme preview scope. When the system processes the `theme[preview_image]` parameter, it fails to sanitize the input before using it in file system operations, creating opportunities for directory traversal sequences such as ../ or ..\ that can navigate to arbitrary locations on the file system. This weakness can be exploited to read sensitive configuration files, database credentials, or other critical system files that should remain protected. The vulnerability's severity is amplified by the fact that it requires only administrative access, which is often a high-privilege account that can be compromised through other means such as credential theft or social engineering attacks.
The operational impact of this vulnerability extends beyond simple file access as it can enable full remote code execution capabilities when combined with other attack vectors or when the attacker has additional system access. An attacker could potentially read application source code, configuration files containing database credentials, or system files that could provide further attack surface. The vulnerability affects multiple versions of Magento Commerce including 2.4.2 and earlier, 2.4.2-p1 and earlier, and 2.3.7 and earlier, indicating a widespread exposure across the Magento platform. Organizations running these affected versions face significant risk of data breaches, system compromise, and potential regulatory violations if sensitive information is accessed through this vulnerability. The attack can result in persistent backdoor access, data exfiltration, and complete system compromise when combined with other exploitation techniques.
Organizations should immediately apply the vendor-provided patches and security updates to address this vulnerability. The mitigation strategy should include implementing proper input validation for all user-supplied parameters, particularly those used in file system operations. Security controls should enforce strict path validation and sanitize all inputs before processing, implementing whitelisting approaches for file access operations. Network segmentation and privileged access controls should be enforced to limit administrative access to only necessary personnel. Regular security assessments and penetration testing should be conducted to identify similar vulnerabilities in the application code. Organizations should also implement monitoring and logging for suspicious file access patterns and unauthorized administrative activities. According to ATT&CK framework, this vulnerability maps to T1059.001 for remote code execution and T1566 for credential access through administrative compromise. The vulnerability demonstrates the critical importance of proper input validation and the principle of least privilege in preventing privilege escalation attacks.