CVE-2026-3325: MegaCMS v12.0.0 SQL Injection Vulnerability

CVE-2026-3325 Overview

A critical SQL injection vulnerability has been identified in MegaCMS v12.0.0, specifically affecting the id_territorio parameter within the /web_comunications/cms/get_provincias endpoint. This vulnerability stems from inadequate validation and sanitization of user input, allowing unauthenticated attackers to execute arbitrary SQL queries against the backend database through a crafted POST request. The vulnerable parameter is processed immediately after the registration form submission, creating a significant attack surface for malicious actors.

Critical Impact
Unauthenticated attackers can execute arbitrary SQL queries, potentially leading to complete database compromise, data exfiltration, data manipulation, and full system takeover.

Affected Products

MegaCMS v12.0.0
MegaCMS CRM Sistemas de Fidelizacion

Discovery Timeline

2026-04-29 - CVE-2026-3325 published to NVD
2026-04-29 - Last updated in NVD database

Technical Details for CVE-2026-3325

Vulnerability Analysis

This SQL injection vulnerability (CWE-89) exists due to the application's failure to properly validate and sanitize user-supplied input before incorporating it into SQL queries. The id_territorio parameter in the /web_comunications/cms/get_provincias endpoint directly accepts user input via POST requests without adequate input filtering or parameterized query implementation.

When a user submits the registration form, the application processes the id_territorio parameter to retrieve province-related data from the database. Because this input is not properly sanitized, an attacker can inject malicious SQL statements that will be executed by the database server with the application's privileges.

The vulnerability is particularly dangerous because it does not require authentication to exploit. Any remote attacker with network access to the affected MegaCMS installation can craft malicious POST requests to the vulnerable endpoint, potentially extracting sensitive data, modifying database contents, or escalating to remote code execution depending on the database configuration.

Root Cause

The root cause of this vulnerability is improper input validation (CWE-89: Improper Neutralization of Special Elements used in an SQL Command). The application fails to implement proper input sanitization or parameterized queries when processing the id_territorio parameter. User-supplied data is directly concatenated into SQL query strings rather than being treated as data separate from the query structure, enabling SQL injection attacks.

Attack Vector

The attack is executed via network-based POST requests targeting the /web_comunications/cms/get_provincias endpoint. An unauthenticated remote attacker can manipulate the id_territorio parameter to inject arbitrary SQL commands. The attack does not require any privileges or user interaction, making it highly exploitable. The vulnerable endpoint processes the registration form data, meaning the attack surface is exposed to any user who can access the registration functionality.

The attacker would craft a POST request to the vulnerable endpoint with a malicious payload in the id_territorio parameter. Classic SQL injection techniques such as UNION-based injection, boolean-based blind injection, or time-based blind injection could be employed to extract data or manipulate the database. For detailed technical information, see the INCIBE Security Notice on SQL Injection.

Detection Methods for CVE-2026-3325

Indicators of Compromise

Unusual POST requests to /web_comunications/cms/get_provincias containing SQL syntax characters such as single quotes, double quotes, semicolons, or SQL keywords
Database error messages in application logs or HTTP responses indicating SQL syntax errors
Unexpected database queries or access patterns in database audit logs
Evidence of data exfiltration or unauthorized database modifications

Detection Strategies

Implement Web Application Firewall (WAF) rules to detect and block SQL injection patterns in POST parameters targeting the /web_comunications/cms/get_provincias endpoint
Enable detailed logging for the affected endpoint and monitor for suspicious id_territorio parameter values containing SQL metacharacters
Deploy database activity monitoring to detect unusual query patterns or unauthorized data access attempts
Configure intrusion detection systems (IDS) with signatures for common SQL injection attack patterns

Monitoring Recommendations

Monitor HTTP access logs for abnormal request patterns to the registration form and related endpoints
Set up alerts for database errors that may indicate SQL injection attempts
Review database query logs for unexpected SELECT, UNION, INSERT, UPDATE, or DELETE statements
Implement real-time monitoring for POST requests containing encoded or obfuscated SQL injection payloads

How to Mitigate CVE-2026-3325

Immediate Actions Required

Restrict network access to the affected /web_comunications/cms/get_provincias endpoint if not required for public access
Implement Web Application Firewall rules to block requests containing SQL injection patterns in the id_territorio parameter
Review database user privileges and apply principle of least privilege to limit potential impact
Enable enhanced logging and monitoring for the affected endpoint to detect exploitation attempts

Patch Information

Organizations should check with the MegaCMS vendor for official security patches addressing this vulnerability. Review the INCIBE Security Notice for additional remediation guidance and updates on patch availability. Until a patch is available, implement the workarounds and detection strategies outlined in this advisory.

Workarounds

Deploy a Web Application Firewall with SQL injection detection rules in front of the MegaCMS application
If possible, disable or restrict access to the /web_comunications/cms/get_provincias endpoint until a patch is applied
Implement input validation at the application level using allowlists for the id_territorio parameter (numeric values only)
Consider implementing parameterized queries or prepared statements at the application code level if source code access is available

bash

# Example WAF rule for ModSecurity to block SQL injection in id_territorio parameter
SecRule ARGS:id_territorio "@detectSQLi" \
    "id:1001,\
    phase:2,\
    block,\
    log,\
    msg:'SQL Injection attempt detected in id_territorio parameter - CVE-2026-3325',\
    severity:'CRITICAL'"