CVE-2026-13430 in Post Export Import with Media Plugin
Summary
by MITRE • 07/10/2026
The Post Export Import with Media plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 1.13.1 via the import_media_file_secure function. This is due to insufficient file extension validation caused by a trailing-dot filename bypass, where the extension allow-list check in ajax_import_media_start() uses pathinfo() on the raw ZIP entry name (e.g., 'shell.php.'), which returns an empty string for the extension, causing the allow-list guard to be skipped and the file to be extracted to a temporary location, after which import_media_file_secure() copies it into the WordPress uploads directory without re-validating the extension. This makes it possible for authenticated attackers, with administrator-level access and above, to upload files that may be executable, which makes remote code execution possible.
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Analysis
by VulDB Data Team • 07/10/2026
The Post Export Import with Media plugin for WordPress presents a critical arbitrary file upload vulnerability affecting all versions up to and including 1.13.1. This vulnerability stems from insufficient input validation within the import_media_file_secure function, creating a pathway for malicious file execution that could compromise entire WordPress installations. The flaw operates through a sophisticated bypass mechanism involving trailing-dot filename manipulation that circumvents standard security controls designed to prevent executable file uploads.
The technical exploitation occurs due to a specific implementation error in the file extension validation process where the system relies on pathinfo() function to examine raw ZIP entry names such as 'shell.php.'. This particular filename format, containing a trailing dot, causes pathinfo() to return an empty string for the file extension, effectively bypassing the allow-list validation mechanism that should prevent uploading of potentially dangerous file types. The vulnerability exists in the ajax_import_media_start() function which processes the initial file validation before proceeding with extraction operations.
Once the malicious file passes the initial validation due to the trailing-dot bypass, the system extracts the file to a temporary location without proper re-validation. Subsequently, the import_media_file_secure() function copies this file directly into the WordPress uploads directory without performing additional extension checks, creating a window of opportunity for attackers to place executable files within the web root. This multi-stage process allows authenticated users with administrator-level privileges or higher to upload malicious files that could include php shells, webshells, or other executable content that would be processed by the web server.
The operational impact of this vulnerability is severe and directly aligns with attack patterns documented in the MITRE ATT&CK framework under T1505.003 for Server-Side Include and T1059.007 for Command and Scripting Interpreter, as it enables attackers to establish persistent access through uploaded webshells. The vulnerability represents a classic example of a path traversal or file validation bypass issue that falls under CWE-434, which specifically addresses insecure file upload vulnerabilities where systems fail to properly validate file types before processing them. Organizations running vulnerable versions of this plugin face significant risk of remote code execution and complete system compromise.
Administrative access is required for exploitation, making the vulnerability particularly dangerous in environments where administrative credentials are compromised or when attackers can escalate privileges through other means. The threat landscape surrounding such vulnerabilities is well-documented in industry reports showing that file upload flaws frequently lead to full system compromises, with attackers using these entry points to establish persistent backdoors, exfiltrate data, or launch further attacks within network environments. Organizations should immediately update to patched versions of the plugin, implement additional security measures such as file type whitelisting at the web server level, and conduct comprehensive security audits of all installed plugins to identify similar vulnerabilities that could be exploited for remote code execution.