CVE-2026-104368 in Export and Import Users and Customers Plugin
Summary
by MITRE • 10/30/2026
The Export and Import Users and Customers plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 2.7.5 via the plugin's own export and re-import workflow. The vulnerability exists because of a CSV escape-character mismatch between the exporter and the importer: class-csvwriter.php writes cells with fputcsv() using PHP's default backslash (\) escape character, while class-csvreader.php parses the same file with fgetcsv() using a double-quote (") as the escape character. As a result, a crafted value stored in a Subscriber's Biographical Info field — containing a backslash-quote sequence followed by a newline — is written as a single quoted CSV field but parsed back as two separate rows on import. The injected second row is then processed by hf_create_customer() as a new user record whose user_login, user_pass, user_email, and role are entirely attacker-controlled, allowing the creation of an arbitrary Administrator account. This makes it possible for authenticated attackers with Subscriber-level access and above to escalate their privileges to Administrator.
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Analysis
by VulDB Data Team • 10/30/2026
The Export and Import Users and Customers plugin for WordPress contains a critical privilege escalation vulnerability affecting all versions up to 2.7.5, rooted in a fundamental inconsistency within its data serialization logic. This flaw allows authenticated attackers with subscriber-level access or higher to escalate their privileges to administrator level by exploiting the mismatch between how user data is exported and subsequently re-imported into the system. The core of this vulnerability lies in the divergent handling of escape characters during CSV processing, specifically involving the Biographical Info field which serves as a vector for injecting malicious payloads that are misinterpreted upon import.
The technical mechanism behind this exploitation involves a discrepancy between the exporter class, class-csvwriter.php, and the importer class, class-csvreader.php. When exporting user data, the writer utilizes PHP's fputcsv function with its default escape character set to backslash. Conversely, when importing data via the same plugin workflow, the reader employs fgetcsv but configures it to use a double-quote as the escape character rather than the expected backslash or no escape at all depending on standard CSV parsing expectations. This configuration mismatch creates a scenario where specific sequences of characters are interpreted differently during write and read operations, leading to structural corruption of the data rows being processed.
An attacker can leverage this inconsistency by crafting a malicious value for their own Biographical Info field that contains a backslash followed by a double-quote sequence, immediately succeeded by a newline character. When the plugin exports this user's data using class-csvwriter.php, the fputcsv function treats the entire string as a single quoted CSV field because of the quoting rules applied during writing. However, when this exported file is re-imported through class-csvreader.php, the fgetcsv function interprets the backslash-quote sequence not as an escaped quote within a field, but as a delimiter or escape that terminates the current row prematurely due to its specific parsing logic for double-quoted fields with different escape rules. Consequently, what was intended as one data record is parsed by the importer as two distinct rows.
The second of these artificially created rows contains attacker-controlled content because it originates from the crafted input in the Biographical Info field. During the import process, this malformed row is passed to the hf_create_customer function, which processes incoming records and creates new user accounts based on the data provided. Since the structure of the injected row allows the attacker to dictate values for critical fields such as user_login, user_pass, user_email, and role, they can effectively define a complete new administrator account without needing valid credentials or administrative approval. This results in the creation of an arbitrary Administrator account that possesses full control over the WordPress installation.
From a security classification perspective, this vulnerability aligns with CWE-269 Improper Privilege Management as it allows a lower-privileged user to gain higher-level access through flawed input validation and processing logic. It also maps to ATT&CK technique T1078 Valid Accounts, where attackers use legitimate credentials to escalate privileges within the system environment. The impact is severe, granting full administrative control over the WordPress site, which can lead to complete compromise of data integrity, confidentiality, and availability for all users and content hosted on that instance.
Mitigation strategies should prioritize immediate updating of the plugin to a patched version where this CSV parsing inconsistency has been resolved by ensuring consistent escape character handling across both export and import modules. In environments where updates cannot be applied immediately, administrators should disable the re-import functionality or restrict access to user management features to trusted users only. Additionally, implementing strict input validation on fields that are subject to serialization processes can help prevent similar injection attacks in other plugins or custom code within the WordPress ecosystem. Regular auditing of CSV handling logic and adherence to RFC 4180 standards for comma-separated values would further reduce the risk of such parsing discrepancies occurring in future developments.