External risk intelligence

MCMS SQL Injection in Custom Model Import

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-88416

The vulnerability exists in a Content Management System (CMS), which is typically deployed as a public-facing web application. Features such as model or form imports are common functions in web-based administrative interfaces that are often accessible over the internet.

SQL Injection

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory details a critical vulnerability in certain versions of a content management system, specifically within its import feature for custom models and forms. The issue allows for unauthorized data access and manipulation due to a SQL injection flaw, potentially impacting system integrity and the confidentiality of stored information. The main concern is confirming relevance and exposure.

A flaw lets attackers misuse a content system's import function.
It impacts system integrity and data confidentiality.
Confirm if this content management system is in use.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending a specially crafted request to the MCMS custom model/form import feature. This feature, if exposed to the internet, allows for the submission of data that is not properly validated before being used in a database query. Successful exploitation could allow an attacker to manipulate database queries, potentially leading to unauthorized access, modification, or deletion of data.

Network access required for entry.
Importing a custom model/form triggers the vulnerability.
Allows database manipulation and data compromise.

Live Threat

Current exploitation, exposure, and threat context

This SQL injection vulnerability in the custom model/form import feature could allow an unauthenticated attacker to execute arbitrary SQL commands. This might lead to unauthorized access to or modification of the system's database when the import feature is accessible.

System database could be compromised.
Malicious SQL commands could be injected.
Unauthorized data access or modification.

Operational Fix

Recommended remediation, mitigation, and detection steps

Given the SQL injection vulnerability in the MCMS custom model/form import feature, the platform or infrastructure team is likely responsible for managing the MCMS deployment. The first practical step is to identify all instances of MCMS, assess their exposure and business criticality, and then locate the specific application or system owner to plan remediation.

Platform/Infrastructure team owns remediation.
Verify MCMS instances and exposure.
Plan remediation based on risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

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Frequently asked questions

What is MCMS?

MCMS is a content management system used to organize digital assets and web data. It provides administrators with specific features to import custom models and forms, which helps define how the application structures and stores information within its backend database.

How is the SQL injection vulnerability classified?

This flaw is identified as CWE-89, or Improper Neutralization of Special Elements used in an SQL Command. It occurs because the software fails to sanitize user-provided data during the custom model or form import process, enabling malicious database queries.

Under what conditions does this vulnerability trigger?

The flaw triggers when the system processes input for custom model or form imports without adequate validation. Because the issue is not limited to authenticated sessions, external network requests to this specific import function can interact with the database.

Why is this specific vulnerability relevant?

As noted by Halo Surface Signal, this issue is likely relevant because it resides in a CMS typically deployed as a public-facing application. Administrative interfaces like import tools are often accessible over the internet, increasing the potential attack surface.

What are the first steps to address this risk?

Infrastructure teams should immediately identify all active MCMS instances across the environment. Once localized, teams must assess the business criticality of these systems, determine their internet exposure, and coordinate with application owners to plan remediation.

References

github.com/15536818056/CVE/issues/3

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.