CVE-2026-16614: WordPress GSheetConnector SQLi Flaw

CVE-2026-16614 Overview

CVE-2026-16614 is an authenticated SQL Injection vulnerability [CWE-89] in the GSheetConnector – CF7 Google Sheets Connector with Real-Time Sync plugin for WordPress. The flaw affects all versions up to and including 5.2.1. The s search parameter is interpolated into a SQL query without sufficient escaping or use of a prepared statement. Attackers with administrator-level privileges can append additional SQL clauses to the existing query and extract sensitive data from the WordPress database.

Critical Impact
Authenticated administrators can exfiltrate database contents by injecting SQL fragments through the s request parameter in the plugin's form entry listing page.

Affected Products

GSheetConnector – CF7 Google Sheets Connector with Real-Time Sync plugin for WordPress
All plugin versions up to and including 5.2.1
WordPress sites where the vulnerable plugin is installed and activated

Discovery Timeline

2026-08-01 - CVE-2026-16614 published to the National Vulnerability Database (NVD)
2026-08-03 - Last updated in NVD database

Technical Details for CVE-2026-16614

Vulnerability Analysis

The vulnerability resides in the plugin's form entry listing logic, specifically in class-gs-cf7db-formEntryList.php and gs-cf7db.php. The plugin reads the s HTTP parameter, passes it through wp_unslash() and sanitize_text_field(), and then interpolates the result directly into a SQL query string. Neither function protects against SQL injection.

wp_unslash() removes the magic-quote backslashes that WordPress applies to superglobals, restoring raw single quotes. sanitize_text_field() strips tags and normalizes whitespace but does not escape SQL metacharacters. The resulting string still contains functional single quotes, comment sequences, and UNION keywords that break out of the surrounding literal.

An attacker with administrator-level access can therefore append arbitrary SQL to the query. Successful exploitation exposes stored form submissions, user records, session tokens, and other data in the WordPress database.

Root Cause

The root cause is unsafe query construction. The plugin never calls $wpdb->prepare() with placeholder binding for the s parameter, and it relies on sanitizers that were designed to filter HTML content rather than SQL syntax. This is a classic case of trusting an input filter that does not address the target injection context.

Attack Vector

Exploitation requires authenticated access at the administrator role or higher and network reachability to the WordPress admin interface. The attacker submits a crafted value in the s query string parameter to the form entry listing page. The injected SQL executes against the WordPress database with the privileges of the WordPress database user. No user interaction beyond the attacker's own session is required.

No public proof-of-concept exploit code is available. See the Wordfence Vulnerability Report and the referenced WordPress Plugin Code Snippet for the vulnerable code paths.

Detection Methods for CVE-2026-16614

Indicators of Compromise

Requests to the plugin's form entry listing page containing SQL metacharacters such as single quotes, UNION SELECT, --, /*, or SLEEP( in the s parameter.
Unexpected wp_users, wp_usermeta, or plugin form-entry table reads originating from the WordPress database user during administrator sessions.
Web server access logs showing long or URL-encoded s query values submitted to admin.php pages associated with the GSheetConnector plugin.

Detection Strategies

Enable WordPress database query logging or MySQL general query logging and alert on SELECT statements referencing the plugin's form entry table that contain injected clauses.
Deploy a Web Application Firewall (WAF) rule that inspects the s parameter for SQL keywords and metacharacters when the request targets GSheetConnector admin pages.
Correlate administrator authentication events with anomalous outbound data volumes to identify database exfiltration following an administrator login.

Monitoring Recommendations

Track administrator account creation, role elevation, and password reset events on WordPress sites running the plugin.
Monitor plugin version inventory and flag installations at version 5.2.1 or earlier.
Alert on repeated 500-series responses from the plugin's admin pages, which can indicate injection probing that breaks query syntax.

How to Mitigate CVE-2026-16614

Immediate Actions Required

Update the GSheetConnector – CF7 Google Sheets Connector with Real-Time Sync plugin to the version released after 5.2.1 that addresses this vulnerability.
Audit WordPress administrator accounts and remove any unused or unnecessary administrator-level users.
Enforce multi-factor authentication (MFA) for all WordPress administrator accounts to reduce the risk of an attacker obtaining the privileges required for exploitation.
Review recent database query logs and administrator activity for signs of exploitation.

Patch Information

The vendor addressed the issue in a subsequent plugin release. Refer to the WordPress Plugin Change Log for the specific code changes that add proper query preparation to the affected code paths.

Workarounds

If patching cannot be performed immediately, deactivate the GSheetConnector plugin until an update is applied.
Restrict access to WordPress administration URLs by source IP address at the web server or WAF layer.
Apply a WAF virtual patch that blocks SQL metacharacters in the s parameter for requests targeting the plugin's form entry listing page.

bash

# Example WAF rule concept (ModSecurity) - adapt to your environment
SecRule ARGS:s "@rx (?i)(union(\s|\+)+select|--|/\*|';|sleep\(|benchmark\()" \
    "id:1026016614,phase:2,deny,status:403,\
    msg:'CVE-2026-16614 GSheetConnector SQLi attempt in s parameter'"