CVE-2026-52700 Overview
CVE-2026-52700 is a SQL injection vulnerability affecting the WCMultiShipping plugin for WordPress in versions up to and including 3.0.2. The flaw allows authenticated users with Subscriber-level privileges to inject malicious SQL statements into database queries. The vulnerability is categorized under [CWE-89] (Improper Neutralization of Special Elements used in an SQL Command). Because exploitation requires only Subscriber privileges, the barrier to entry is low on sites that permit open user registration.
Critical Impact
An authenticated Subscriber can manipulate backend SQL queries to extract sensitive database contents from WordPress installations running WCMultiShipping 3.0.2 or earlier.
Affected Products
- WCMultiShipping WordPress plugin versions <= 3.0.2
- WordPress sites with WCMultiShipping installed and open user registration
- WooCommerce-based stores using WCMultiShipping for shipping management
Discovery Timeline
- 2026-06-15 - CVE-2026-52700 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2026-52700
Vulnerability Analysis
The vulnerability is a SQL injection flaw in the WCMultiShipping plugin. It allows an attacker holding a low-privilege Subscriber account to send crafted input that is concatenated into a SQL query without proper sanitization or parameterization. Because the scope is marked as changed in the CVSS vector, successful exploitation can affect resources beyond the vulnerable component itself, including the underlying WordPress database.
The primary impact is confidentiality. An attacker can read arbitrary data from the WordPress database, including user credentials, session tokens, order information, and customer personally identifiable information (PII). Secondary availability impact is also possible if injected queries trigger expensive operations or table locks.
Root Cause
The root cause is improper neutralization of user-controlled input within a SQL statement [CWE-89]. The plugin accepts request parameters from an authenticated Subscriber and passes them into a database query without using prepared statements or the WordPress $wpdb->prepare() API. This permits attacker-supplied SQL fragments to be interpreted as query syntax rather than data.
Attack Vector
The attack vector is network-based and requires authentication at the Subscriber level. After registering or compromising a low-privilege account, the attacker sends an HTTP request to the vulnerable plugin endpoint with a payload containing SQL metacharacters. The injected payload alters the query logic to return data the attacker is not authorized to read. No user interaction is required beyond the attacker's own authenticated session. Refer to the Patchstack Vulnerability Analysis for the technical write-up.
Detection Methods for CVE-2026-52700
Indicators of Compromise
- HTTP requests to WCMultiShipping plugin endpoints containing SQL metacharacters such as UNION SELECT, SLEEP(, OR 1=1, or --.
- Unexpected database query errors in WordPress or PHP logs originating from the wc-multishipping plugin path.
- Subscriber-level accounts issuing repeated requests to plugin AJAX or REST endpoints not normally used by low-privilege users.
- Anomalous spikes in database CPU or query latency correlated with WCMultiShipping endpoint traffic.
Detection Strategies
- Inspect web server access logs for query string and POST body content containing SQL keywords directed at WCMultiShipping endpoints.
- Enable WordPress query logging or SAVEQUERIES in staging to identify non-parameterized queries originating from the plugin.
- Deploy a Web Application Firewall (WAF) rule set with SQL injection signatures tuned for WordPress plugin paths.
Monitoring Recommendations
- Alert on newly registered Subscriber accounts that immediately interact with plugin endpoints.
- Monitor outbound database query patterns for information_schema access from PHP-FPM workers serving WordPress.
- Track WordPress audit logs for unusual data export or read patterns tied to Subscriber sessions.
How to Mitigate CVE-2026-52700
Immediate Actions Required
- Update WCMultiShipping to a version newer than 3.0.2 once a patched release is published by the vendor.
- Audit existing Subscriber accounts and remove any that are unrecognized or inactive.
- Disable open user registration in WordPress until the plugin is patched if it is not required for site operation.
- Place a WAF rule in front of WordPress to block SQL injection patterns targeting wc-multishipping request paths.
Patch Information
Consult the Patchstack Vulnerability Analysis for the latest patch status and fixed version information from the plugin maintainer.
Workarounds
- Temporarily deactivate the WCMultiShipping plugin until a fixed version is installed.
- Restrict access to plugin endpoints via web server rules limiting requests to administrator IP ranges.
- Enforce least-privilege by setting users_can_register to false in WordPress settings while a patch is pending.
# Disable open registration via WP-CLI while awaiting a patched release
wp option update users_can_register 0
# Deactivate the vulnerable plugin
wp plugin deactivate wc-multishipping
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
