CVE-2021-21029 in Magento
Summary
by MITRE • 02/12/2021
Magento versions 2.4.1 (and earlier), 2.4.0-p1 (and earlier) and 2.3.6 (and earlier) are affected by a Reflected Cross-site Scripting vulnerability via 'file' parameter. Successful exploitation could lead to arbitrary JavaScript execution in the victim's browser. Access to the admin console is required for successful exploitation.
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Analysis
by VulDB Data Team • 02/28/2021
This vulnerability resides in the Magento e-commerce platform where attackers can exploit a reflected cross-site scripting flaw through the 'file' parameter in specific version ranges. The vulnerability affects Magento 2.4.1 and earlier versions, 2.4.0-p1 and earlier versions, and 2.3.6 and earlier versions, making it a widespread issue across multiple release lines. The reflected XSS vulnerability occurs when user input is not properly sanitized before being returned in HTTP responses, allowing malicious scripts to be executed in the victim's browser context. The attack requires an attacker to have access to the admin console, which provides a crucial access vector for privilege escalation and session hijacking operations. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, and it can be mapped to ATT&CK technique T1566.001 for initial access through malicious links or email attachments that leverage the reflected XSS vulnerability.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding in the file parameter handling within Magento's administrative interface. When administrators navigate to certain administrative pages that process the file parameter, the application fails to properly escape or filter user-supplied input before rendering it in the response. This creates an opportunity for attackers to inject malicious JavaScript code that gets executed when the page loads in the victim's browser. The requirement for admin console access indicates that this is not a direct public attack vector but rather a privilege escalation vulnerability that can be exploited by attackers who have already gained some level of access to the administrative environment. The attack typically involves crafting malicious URLs with specially formatted file parameters that contain JavaScript payloads designed to steal session cookies, redirect users to malicious sites, or perform other harmful actions.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to fully compromise administrative sessions and gain complete control over the Magento store. Successful exploitation allows attackers to access sensitive customer data, modify product information, change pricing, manipulate inventory, and potentially install malware on the server. The admin console access requirement means that attackers who have already compromised other parts of the system can leverage this vulnerability to escalate privileges and maintain persistent access. The reflected nature of the XSS means that the attack can be delivered through various channels including email phishing campaigns, compromised web pages, or social engineering tactics that direct administrators to malicious URLs. This vulnerability can also serve as a stepping stone for more sophisticated attacks such as credential theft, session hijacking, or lateral movement within the network infrastructure.
Mitigation strategies for this vulnerability should include immediate patching of affected Magento versions to the latest releases that contain security fixes for the reflected XSS issue. Organizations should implement proper input validation and output encoding mechanisms throughout the application to prevent similar vulnerabilities from occurring in other components. Web Application Firewalls should be configured to detect and block malicious payloads targeting the file parameter, while also implementing Content Security Policy headers to restrict script execution. Administrative access should be strictly controlled through multi-factor authentication and least privilege principles to limit the potential impact of any successful exploitation attempts. Regular security assessments and penetration testing should be conducted to identify and remediate similar vulnerabilities in the application code. Additionally, security awareness training for administrators should be implemented to prevent social engineering attacks that might lead to exploitation of this vulnerability through phishing or malicious link delivery methods.