CVE-2017-20254: Joomla User Bench SQLi Vulnerability

CVE-2017-20254 Overview

CVE-2017-20254 is an SQL injection vulnerability [CWE-89] in the Joomla! User Bench 1.0 extension. The flaw exists in the userid parameter of the com_userbench component when accessed through index.php with the view=detail view. Unauthenticated attackers can send crafted GET requests to inject arbitrary SQL queries against the backend database. Successful exploitation exposes sensitive data including user credentials and Joomla configuration values.

Critical Impact
Remote unauthenticated attackers can extract database credentials and configuration data through the userid parameter, leading to full compromise of the Joomla site backend.

Affected Products

Joomla! Component User Bench 1.0
Joomla! sites with the User Bench extension installed
Any deployment exposing index.php?option=com_userbench&view=detail publicly

Discovery Timeline

2026-06-19 - CVE-2017-20254 published to the National Vulnerability Database (NVD)
2026-06-22 - Last updated in NVD database

Technical Details for CVE-2017-20254

Vulnerability Analysis

The vulnerability resides in how the Joomla! User Bench 1.0 component handles the userid GET parameter. The component concatenates the userid value directly into an SQL query without parameterization or input sanitization. An attacker can append SQL syntax such as UNION SELECT statements to the parameter to read arbitrary data from the database.

Because exploitation requires no authentication, any internet-accessible Joomla site running this component is exposed. The component is part of the Joomla Extensions Directory ecosystem and is mapped to [CWE-89: Improper Neutralization of Special Elements used in an SQL Command]. A public proof-of-concept is documented in Exploit-DB #43357.

Root Cause

The root cause is improper neutralization of user-supplied input in SQL query construction. The userid parameter received via the URL is passed directly into a query against the Joomla database without using prepared statements or the Joomla database API's escaping methods such as $db->quote() or $db->escape().

Attack Vector

The attack vector is network-based and unauthenticated. An attacker sends a GET request to index.php with option=com_userbench&view=detail&userid=<payload>. The payload contains SQL injection syntax that manipulates the original query to return data from arbitrary tables, including the Joomla #__users table. Refer to the VulnCheck SQL Injection Advisory for technical specifics.

No verified exploit code is included here. See the linked external advisories for complete payload details.

Detection Methods for CVE-2017-20254

Indicators of Compromise

HTTP GET requests to index.php containing option=com_userbench&view=detail&userid= followed by SQL syntax such as UNION, SELECT, SLEEP, --, or '.
Unexpected database error messages in Joomla logs referencing the #__userbench or #__users tables.
Web server access logs showing repeated requests to the User Bench detail view from a single source IP.
Outbound queries or anomalous read activity against the Joomla #__users table outside normal application flows.

Detection Strategies

Inspect web server access logs for com_userbench requests where the userid parameter contains non-numeric characters.
Deploy web application firewall (WAF) signatures that match SQL injection payloads on Joomla endpoint parameters.
Correlate database query logs with HTTP request logs to identify queries originating from the User Bench component that reference unexpected tables.

Monitoring Recommendations

Enable Joomla's debug and database query logging on affected sites until the extension is removed or patched.
Forward web server and database logs to a centralized analytics platform for behavioral baselining of the userid parameter.
Alert on HTTP 500 responses from com_userbench endpoints, which often indicate SQL syntax errors triggered by injection attempts.

How to Mitigate CVE-2017-20254

Immediate Actions Required

Disable or uninstall the Joomla! User Bench 1.0 extension from the Joomla Extensions Manager until a vendor-supplied fix is verified.
Block external access to URLs containing option=com_userbench at the WAF or reverse proxy layer.
Rotate Joomla administrator credentials and any database accounts that may have been exposed.
Audit the #__users table and Joomla configuration for unauthorized modifications.

Patch Information

No vendor patch is referenced in the available advisory data. Administrators should consult the Joomla Extension Documentation and the VulnCheck SQL Injection Advisory for the latest remediation status. If no maintained release is available, replace the User Bench extension with a supported alternative.

Workarounds

Add a WAF rule rejecting requests where the userid parameter contains non-integer characters.
Restrict access to index.php?option=com_userbench to authenticated administrative IP ranges via web server access controls.
Apply database-level least privilege so the Joomla application account cannot read sensitive tables outside its required scope.

bash

# Example nginx rule to block non-numeric userid values on the User Bench endpoint
if ($args ~* "option=com_userbench.*userid=[^0-9&]") {
    return 403;
}