CVE-2026-68000: MCMS SQL Injection Vulnerability

CVE-2026-68000 Overview

CVE-2026-68000 is an unauthenticated SQL injection vulnerability in MCMS versions 6.2.0 and earlier. The flaw resides in the /cms/category/list front-end interface. The size parameter is concatenated directly into the SQL LIMIT clause through the FreeMarker ${size} expression without parameterized binding. The built-in SqlInjectionUtil filter uses a regular-expression blacklist that omits keywords such as CREATE, TABLE, SET, PREPARE, and EXECUTE, enabling filter bypass. Attackers can issue stacked SQL statements against the backend database without authentication.

Critical Impact
Remote, unauthenticated attackers can execute arbitrary stacked SQL statements against MCMS databases, enabling data theft, tampering, and potential downstream code execution through database features.

Affected Products

MCMS versions <= 6.2.0
MCMS front-end endpoint /cms/category/list
Deployments relying on the built-in SqlInjectionUtil blacklist filter

Discovery Timeline

2026-08-26 - CVE-2026-68000 published to NVD
2026-08-26 - Last updated in NVD database

Technical Details for CVE-2026-68000

Vulnerability Analysis

The vulnerability is a SQL injection [CWE-89] in the MCMS content management system. The /cms/category/list endpoint accepts a size parameter that flows into a SQL LIMIT clause. Instead of binding the value as a prepared-statement parameter, MCMS renders it through a FreeMarker template using the ${size} expression. FreeMarker performs plain string substitution, producing a dynamically concatenated SQL query.

Because the endpoint is exposed on the front-end without an authentication requirement, any network-adjacent attacker who can reach the web server can supply crafted input. Successful exploitation permits stacked query execution, meaning multiple SQL statements can be delivered in a single request separated by semicolons.

Root Cause

The root cause is unsafe template-driven query construction combined with a deny-list sanitizer. SqlInjectionUtil attempts to block injection by matching a fixed set of dangerous SQL keywords with regular expressions. The blacklist omits CREATE, TABLE, SET, PREPARE, and EXECUTE. Attackers use these unfiltered keywords to build payloads that reach the database engine intact. Deny-list filtering is inherently brittle; safe query composition requires parameter binding, not keyword rejection.

Attack Vector

An unauthenticated remote attacker sends an HTTP request to /cms/category/list with a malicious size parameter. The payload closes the numeric context of the LIMIT clause and appends additional statements. Using keywords absent from the blacklist, the attacker can create temporary tables, set session variables, or prepare and execute dynamic SQL. This allows extraction of sensitive tables, credential material, and site content, or modification of records. Depending on database privileges and enabled features, escalation to file write or command execution is possible.

Refer to the GitHub PoC for SQL Injection for request-level details.

Detection Methods for CVE-2026-68000

Indicators of Compromise

HTTP requests to /cms/category/list containing unusually large or non-numeric size parameter values
Presence of SQL keywords such as CREATE, PREPARE, EXECUTE, or SET inside the size query-string parameter
Unexpected database sessions running stacked statements originating from the MCMS application user
New or transient tables and prepared statements created by the MCMS database account

Detection Strategies

Deploy web application firewall (WAF) rules that inspect the size parameter for non-integer values on the /cms/category/list route
Enable database query logging and alert on stacked statements or DDL commands issued by the MCMS service account
Correlate anomalous HTTP 200 responses on /cms/category/list with elevated database CPU or row-scan activity

Monitoring Recommendations

Baseline normal request patterns to /cms/category/list and alert on parameter values outside expected numeric ranges
Forward MCMS access logs and database audit logs to a central analytics platform for cross-source correlation
Track outbound data volumes from the MCMS backend database to detect bulk exfiltration following injection attempts

How to Mitigate CVE-2026-68000

Immediate Actions Required

Restrict network access to the MCMS /cms/category/list endpoint at the perimeter or reverse proxy until a patch is applied
Enforce strict integer validation on the size parameter through a WAF or ingress filter
Rotate database credentials used by the MCMS application and review recent database audit logs for signs of exploitation
Reduce the MCMS database account privileges to the minimum required for normal operation

Patch Information

No vendor advisory URL was published in the NVD entry at the time of writing. Operators should monitor the MCMS project for a release above 6.2.0 that replaces ${size} template concatenation with parameterized query binding and removes reliance on the SqlInjectionUtil blacklist. Track the public PoC repository for updates that reference an official fix.

Workarounds

Add a request-filter rule that rejects any value for size that is not a positive integer within an expected range
Extend SqlInjectionUtil or an upstream filter to block the missing keywords CREATE, TABLE, SET, PREPARE, and EXECUTE, while recognizing that keyword filtering is a temporary control
Disable stacked-query support in the database driver configuration where feasible
Place the MCMS instance behind authenticated access controls until an upstream patch is available

bash

# Example nginx rule rejecting non-integer size values on the vulnerable path
location /cms/category/list {
    if ($arg_size !~ "^[0-9]{1,4}$") {
        return 400;
    }
    proxy_pass http://mcms_backend;
}