CVE-2022-45448 in M4 PDF Plugin
Summary
by MITRE • 09/20/2023
M4 PDF plugin for Prestashop sites, in its 3.2.3 version and before, is vulnerable to an arbitrary HTML Document crafting vulnerability. The resource /m4pdf/pdf.php uses templates to dynamically create documents. In the case that the template does not exist, the application will return a fixed document with a message in mpdf format. An attacker could exploit this vulnerability by inputting a valid HTML/CSS document as the value of the parameter.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/13/2023
The vulnerability identified as CVE-2022-45448 affects the M4 PDF plugin for PrestaShop e-commerce platforms, specifically versions 3.2.3 and earlier. This issue resides within the plugin's handling of document generation processes through the /m4pdf/pdf.php endpoint which utilizes template-based document creation. The flaw represents a significant security weakness that can be exploited to manipulate the PDF generation process through improper input validation and sanitization mechanisms.
The technical implementation of this vulnerability stems from the plugin's inadequate handling of missing template files. When a requested template does not exist within the system, the application falls back to displaying a default document containing a message formatted in mpdf format. This fallback mechanism becomes exploitable when an attacker can manipulate input parameters to inject malicious HTML and CSS content directly into the document generation process. The vulnerability essentially allows an attacker to bypass normal template processing and inject arbitrary content that gets rendered within the PDF document, creating a potential vector for cross-site scripting attacks and content injection.
From an operational perspective, this vulnerability poses substantial risks to PrestaShop merchants and their customers. An attacker could leverage this flaw to inject malicious scripts, steal sensitive information, or manipulate the content of PDF documents that customers receive. The impact extends beyond simple content manipulation as it could enable more sophisticated attacks including session hijacking, data exfiltration, or the delivery of malicious payloads through PDF documents. The vulnerability affects the entire PrestaShop ecosystem where this plugin is installed, potentially compromising thousands of online stores if not addressed promptly.
Security mitigations for CVE-2022-45448 should focus on immediate patching of the affected M4 PDF plugin to version 3.2.4 or later, which contains the necessary fixes for input validation and sanitization. Organizations should implement proper parameter validation at the input stage, ensuring that all user-supplied content undergoes strict sanitization before being processed by the PDF generation engine. Input filtering mechanisms must be strengthened to prevent HTML and CSS injection attempts, while the fallback mechanism should be secured to prevent arbitrary content injection. This vulnerability aligns with CWE-79 which addresses Cross-Site Scripting flaws and potentially maps to ATT&CK technique T1203 for Exploitation for Client Execution, as the malicious code could be executed when customers open the compromised PDF documents.
The broader implications of this vulnerability highlight the critical need for proper input validation in web applications, particularly in components that handle document generation and user content. The flaw demonstrates how seemingly benign fallback behaviors can become security risks when not properly secured. Organizations should conduct comprehensive security assessments of their e-commerce platforms, reviewing all third-party plugins for similar vulnerabilities and implementing robust security monitoring to detect potential exploitation attempts. The vulnerability also emphasizes the importance of keeping all software components updated and maintaining secure coding practices that prevent injection attacks through user-controllable inputs.