CVE-2024-13544 in Paid Download Plugin
Summary
by MITRE • 02/11/2025
The Zarinpal Paid Download WordPress plugin through 2.3 does not properly validate uploaded files, allowing high privilege users such as admin to upload arbitrary files on the server even when they should not be allowed to (for example in multisite setup)
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Analysis
by VulDB Data Team • 02/11/2025
The vulnerability identified as CVE-2024-13544 affects the Zarinpal Paid Download WordPress plugin version 2.3 and earlier, presenting a critical file upload validation flaw that undermines the security posture of WordPress installations. This issue stems from inadequate input validation mechanisms within the plugin's file handling processes, creating a pathway for unauthorized file execution on affected systems. The vulnerability specifically targets high-privilege users such as administrators, who possess elevated permissions within the WordPress environment, yet the flaw allows these users to bypass normal restrictions that should prevent arbitrary file uploads.
The technical implementation of this vulnerability resides in the plugin's failure to enforce proper file type validation and sanitization during the upload process. When administrators or other high-privilege users attempt to upload files through the plugin interface, the system does not adequately verify the file extensions, MIME types, or content signatures that should normally restrict uploads to safe file formats. This weakness creates a direct attack vector where malicious files can be uploaded to the server, potentially including web shells, malware, or other executable content that could compromise the entire WordPress installation.
From an operational impact perspective, this vulnerability poses significant risks to WordPress multisite environments where strict access controls and security boundaries are expected to be maintained. In multisite configurations, the vulnerability becomes particularly dangerous as it allows privilege escalation within the network of interconnected sites, potentially enabling attackers to gain persistent access across multiple WordPress installations. The implications extend beyond individual site compromise to threaten the broader network infrastructure, especially when administrators may have access to multiple sites within the multisite network.
The vulnerability aligns with CWE-434, which addresses "Unrestricted Upload of File with Dangerous Type," and represents a clear violation of secure coding practices that should prevent file upload functionalities from accepting potentially harmful content. From an ATT&CK framework perspective, this vulnerability maps to T1190 "Exploit Public-Facing Application" and T1059 "Command and Scripting Interpreter" as it enables attackers to upload malicious payloads that can be executed within the target environment. The attack surface expands significantly when considering that administrators typically have elevated privileges and may not be restricted by the same security policies that apply to regular users, making this vector particularly dangerous.
Mitigation strategies should include immediate plugin updates to versions that address the file validation flaw, implementation of additional security layers such as web application firewalls, and restriction of file upload capabilities to only essential file types. Organizations should also conduct thorough security audits of their WordPress installations to identify any other plugins or themes that may exhibit similar vulnerabilities. Network segmentation and monitoring of file upload activities can provide additional defense-in-depth measures to detect and prevent exploitation attempts. Regular security assessments and vulnerability scanning should be implemented to ensure that similar issues are not present in other components of the WordPress ecosystem, particularly in multisite configurations where the attack surface is expanded.