CVE-2026-29909: Mrcms Information Disclosure Vulnerability

CVE-2026-29909 Overview

MRCMS V3.1.2 contains an unauthenticated directory enumeration vulnerability in the file management module. The /admin/file/list.do endpoint lacks authentication controls and proper input validation, allowing remote attackers to enumerate directory contents on the server without any credentials. This improper input validation flaw (CWE-20) enables unauthorized reconnaissance of the server's file system structure.

Critical Impact

Attackers can remotely enumerate directory contents without authentication, potentially exposing sensitive file paths, configuration files, and system structure information that could facilitate further attacks.

Affected Products

• MRCMS version 3.1.2
• MRCMS file management module (/admin/file/list.do endpoint)

Discovery Timeline

• 2026-03-30 - CVE-2026-29909 published to NVD
• 2026-04-02 - Last updated in NVD database

Technical Details for CVE-2026-29909

Vulnerability Analysis

This vulnerability stems from missing authentication controls on the /admin/file/list.do endpoint within MRCMS's file management module. Despite being located under the /admin/ path, this endpoint fails to verify user credentials before processing requests. Combined with improper input validation, attackers can traverse and enumerate directory contents on the target server without any authentication requirements.

The attack can be executed remotely over the network with low complexity, requiring no privileges or user interaction. While the vulnerability only enables information disclosure without direct integrity or availability impact, the exposed directory structure could reveal sensitive paths, backup files, configuration locations, and other information valuable for planning subsequent attacks.

Root Cause

The root cause is improper input validation (CWE-20) combined with missing authentication on administrative endpoints. The /admin/file/list.do endpoint processes directory listing requests without:

1. Verifying that the requesting user is authenticated
2. Validating or sanitizing the directory path input
3. Restricting enumerable paths to permitted directories

This allows unauthenticated users to query arbitrary directory paths and receive their contents.

Attack Vector

The attack is network-based and can be exploited by sending crafted HTTP requests to the vulnerable endpoint. An attacker would target the /admin/file/list.do endpoint with directory path parameters to enumerate server directories remotely. No special privileges, credentials, or user interaction are required to exploit this vulnerability.

The vulnerability allows attackers to systematically map the server's file system structure, potentially identifying sensitive configuration files, backup directories, upload locations, and other high-value targets for further exploitation.

Detection Methods for CVE-2026-29909

Indicators of Compromise

• Unusual HTTP requests to /admin/file/list.do from unauthenticated sessions or unknown IP addresses
• Multiple rapid requests to the file listing endpoint with varying path parameters
• Access logs showing directory enumeration patterns from external sources
• Requests to administrative endpoints without corresponding authentication events

Detection Strategies

• Monitor web server access logs for requests to /admin/file/list.do without valid session cookies
• Implement web application firewall (WAF) rules to detect directory traversal patterns
• Alert on high-volume requests to file management endpoints from single IP addresses
• Deploy anomaly detection for unauthenticated access to administrative paths

Monitoring Recommendations

• Enable detailed logging for all requests to /admin/* endpoints
• Configure SIEM rules to correlate file listing requests with authentication events
• Monitor for sequential directory enumeration patterns in application logs
• Review access patterns to identify potential reconnaissance activity

How to Mitigate CVE-2026-29909

Immediate Actions Required

• Implement authentication checks on the /admin/file/list.do endpoint immediately
• Restrict access to administrative paths at the web server or reverse proxy level
• Review and audit all endpoints under /admin/ for similar authentication gaps
• Consider temporarily disabling the file management module if not critical

Patch Information

No vendor patch has been released at the time of this writing. System administrators should implement compensating controls until an official fix is available. For more information, refer to the MRCMS GitHub Repository and the proof-of-concept documentation.

Workarounds

• Configure web server or reverse proxy rules to require authentication for all /admin/* paths
• Implement IP-based access restrictions to limit administrative endpoint access to trusted networks
• Deploy a web application firewall (WAF) with rules to block unauthenticated requests to administrative endpoints
• Consider upgrading or migrating to an actively maintained CMS if patches are not forthcoming

# Example nginx configuration to restrict admin endpoints
location /admin/ {
    # Require authentication or restrict by IP
    allow 10.0.0.0/8;
    allow 192.168.0.0/16;
    deny all;
    
    # Or implement basic authentication as temporary measure
    # auth_basic "Admin Access";
    # auth_basic_user_file /etc/nginx/.htpasswd;
}