CVE-2026-5780: MphRx Minerva IDOR Vulnerability Exposed

CVE-2026-5780 Overview

An insecure direct object reference (IDOR) vulnerability has been identified in MphRx's Minerva V3.6.0, specifically affecting the /minerva/moUser/show/ endpoint. This access control flaw allows authenticated users to bypass authorization controls and access sensitive data belonging to other registered users by simply manipulating the ID parameter in API requests. Successful exploitation enables attackers to enumerate and extract user information across the entire application.

Critical Impact

Authenticated attackers can harvest sensitive user data from the entire Minerva platform by iterating through user IDs, potentially exposing personal information, credentials, and other protected data.

Affected Products

• MphRx Minerva V3.6.0
• Minerva platform deployments using the /minerva/moUser/show/ endpoint
• Systems with user enumeration functionality accessible to authenticated users

Discovery Timeline

• April 28, 2026 - CVE-2026-5780 published to NVD
• April 28, 2026 - Last updated in NVD database

Technical Details for CVE-2026-5780

Vulnerability Analysis

This vulnerability represents a classic Insecure Direct Object Reference (IDOR) flaw, categorized under CWE-284 (Improper Access Control). The application fails to properly validate whether the authenticated user making a request is authorized to access the specific resource identified by the ID parameter.

The vulnerability is network-exploitable with low attack complexity, requiring only basic authentication to the Minerva platform. No user interaction is needed for exploitation, making it particularly dangerous in multi-tenant environments where user data isolation is critical.

The impact extends beyond the immediate vulnerability scope, as successful exploitation can lead to high confidentiality impact on both the vulnerable system and potentially connected systems, along with high integrity impact on subsequent systems that rely on the exposed user data.

Root Cause

The root cause of this vulnerability lies in the absence of proper authorization checks in the /minerva/moUser/show/ endpoint. When processing requests, the application validates that the user is authenticated but fails to verify whether the authenticated user has permission to access the specific user record identified by the ID parameter. This missing access control allows horizontal privilege escalation, where one authenticated user can access data belonging to other users at the same privilege level.

Attack Vector

The attack leverages the network-accessible API endpoint to exploit the broken access control mechanism. An attacker who has obtained legitimate authentication credentials to the Minerva platform can manipulate the ID parameter in requests to the /minerva/moUser/show/ endpoint.

The exploitation process involves making authenticated requests while incrementing or enumerating the user ID parameter. Since the application does not validate ownership or access rights to the requested resource, each modified request returns data for the corresponding user ID, allowing systematic data harvesting.

For example, an authenticated attacker could iterate through sequential ID values to build a comprehensive list of all users in the system, extracting whatever user data the endpoint exposes. The vulnerability requires no special privileges beyond basic authenticated access, making it accessible to any legitimate user of the platform.

For detailed technical information, refer to the INCIBE CERT Vulnerability Notice.

Detection Methods for CVE-2026-5780

Indicators of Compromise

• Unusual patterns of sequential or rapid requests to the /minerva/moUser/show/ endpoint from a single authenticated session
• Authenticated users accessing user records outside their normal scope or organizational boundaries
• Elevated volume of API calls to user enumeration endpoints compared to baseline behavior
• Access logs showing a single user account retrieving data for multiple distinct user IDs in rapid succession

Detection Strategies

• Implement API monitoring to detect anomalous access patterns on the /minerva/moUser/show/ endpoint
• Configure rate limiting alerts for repeated requests with varying ID parameters from the same session
• Deploy web application firewall (WAF) rules to flag sequential ID enumeration attempts
• Enable detailed access logging for user data endpoints to support forensic analysis

Monitoring Recommendations

• Establish baseline metrics for normal user data access patterns and alert on statistical deviations
• Monitor authentication logs for accounts exhibiting reconnaissance behavior across multiple user records
• Implement real-time alerting for bulk data access attempts on user management endpoints
• Review access logs regularly for evidence of IDOR exploitation attempts

How to Mitigate CVE-2026-5780

Immediate Actions Required

• Implement server-side authorization checks to validate that the authenticated user has permission to access the requested user record
• Consider temporarily restricting access to the /minerva/moUser/show/ endpoint until a proper fix is deployed
• Review and audit all similar API endpoints for potential IDOR vulnerabilities
• Enable enhanced logging on affected endpoints to detect ongoing exploitation attempts

Patch Information

Administrators should consult MphRx for official patch availability and upgrade guidance. Review the INCIBE CERT Vulnerability Notice for the latest remediation information and vendor communications.

Organizations running MphRx Minerva V3.6.0 should prioritize applying security updates when available and implement compensating controls in the interim.

Workarounds

• Implement network-level access controls to restrict which users and IP ranges can access the Minerva user management API
• Deploy a reverse proxy or API gateway with custom authorization logic to validate user access rights before forwarding requests
• Configure application-level rate limiting to mitigate automated enumeration attempts
• Consider implementing opaque identifiers (such as UUIDs) instead of sequential IDs to reduce enumeration feasibility

# Example: Nginx rate limiting configuration for the affected endpoint
limit_req_zone $binary_remote_addr zone=minerva_user_api:10m rate=10r/m;

location /minerva/moUser/show/ {
    limit_req zone=minerva_user_api burst=5 nodelay;
    # Additional access controls recommended
    allow 10.0.0.0/8;
    deny all;
}