CVE-2025-40659: DM Corporative CMS Auth Bypass Flaw

CVE-2025-40659 Overview

An Insecure Direct Object Reference (IDOR) vulnerability has been discovered in DM Corporative CMS. This vulnerability allows an unauthenticated attacker to access private administrative areas by manipulating the option parameter in the /administer/selectionnode/framesSelectionNetworks.asp endpoint. By setting the option parameter to values 0, 1, or 2, attackers can bypass access controls and gain unauthorized access to restricted functionality.

Critical Impact

Unauthorized access to private administrative areas allows attackers to view sensitive information and potentially compromise the content management system's security posture.

Affected Products

• DM Corporative CMS (all versions)
• ACC DM Corporative CMS
• DMacroWeb CMS platform

Discovery Timeline

• 2025-06-10 - CVE-2025-40659 published to NVD
• 2025-10-22 - Last updated in NVD database

Technical Details for CVE-2025-40659

Vulnerability Analysis

This vulnerability falls under CWE-639: Authorization Bypass Through User-Controlled Key, commonly known as Insecure Direct Object Reference (IDOR). The flaw exists in how the DM Corporative CMS handles authorization checks for the framesSelectionNetworks.asp administrative endpoint. The application fails to properly validate whether a user is authenticated and authorized before granting access to sensitive administrative functionality.

The vulnerability can be exploited remotely over the network without requiring any authentication or user interaction. An attacker can directly access the private administrative area by crafting requests to the vulnerable endpoint with specific parameter values, completely bypassing the intended access control mechanisms.

Root Cause

The root cause of this vulnerability is insufficient authorization validation in the framesSelectionNetworks.asp file. The application relies solely on client-controllable parameter values to determine access privileges rather than implementing proper server-side session validation and role-based access controls. When the option parameter is set to specific integer values (0, 1, or 2), the application grants access to protected functionality without verifying the requester's identity or permissions.

Attack Vector

The attack is network-based and requires no authentication or special privileges. An attacker can exploit this vulnerability by simply sending HTTP requests to the vulnerable endpoint:

The vulnerability is exploited by accessing the endpoint /administer/selectionnode/framesSelectionNetworks.asp and manipulating the option parameter. Setting this parameter to values 0, 1, or 2 bypasses the intended access controls. For example, a request to /administer/selectionnode/framesSelectionNetworks.asp?option=0 would grant unauthorized access to the private administrative area. No authentication tokens, session cookies, or other credentials are required for exploitation.

For complete technical details, refer to the INCIBE Security Notice.

Detection Methods for CVE-2025-40659

Indicators of Compromise

• Unusual HTTP requests to /administer/selectionnode/framesSelectionNetworks.asp from unauthenticated sources
• Access logs showing requests with option=0, option=1, or option=2 parameters from external IP addresses
• Unexpected access patterns to administrative endpoints without corresponding authentication events
• Multiple requests probing various parameter values on administrative ASP endpoints

Detection Strategies

• Configure web application firewall (WAF) rules to monitor and alert on direct access attempts to /administer/ paths without valid session tokens
• Implement anomaly detection for requests to administrative endpoints that do not follow normal authentication flows
• Create SIEM correlation rules to identify parameter manipulation attacks targeting access control endpoints
• Monitor for reconnaissance activity involving enumeration of ASP administrative endpoints

Monitoring Recommendations

• Enable detailed access logging for all requests to the /administer/ directory structure
• Configure real-time alerting for unauthorized access attempts to administrative endpoints
• Implement rate limiting on administrative paths to slow down automated exploitation attempts
• Review web server logs regularly for suspicious patterns targeting framesSelectionNetworks.asp

How to Mitigate CVE-2025-40659

Immediate Actions Required

• Restrict access to the /administer/ directory using IP-based allowlisting at the web server or firewall level
• Implement authentication requirements at the web server level for all administrative endpoints
• Review and audit all ASP files in the administrative directory for similar IDOR vulnerabilities
• Consider taking the administrative interface offline until proper access controls are implemented

Patch Information

Organizations should consult the INCIBE Security Notice for the latest information regarding patches and updates from the vendor. Contact ACC (the vendor) directly to inquire about security updates addressing this vulnerability.

Workarounds

• Implement server-side access controls using .htaccess or IIS URL Authorization rules to require authentication for all administrative paths
• Deploy a reverse proxy or WAF in front of the application to enforce authentication before requests reach the CMS
• Use network segmentation to ensure administrative endpoints are only accessible from trusted internal networks
• Add custom authentication middleware at the web server level to validate sessions before passing requests to ASP scripts

# IIS URL Authorization example - web.config
# Add to the /administer/ directory to require authentication
# <configuration>
#   <system.webServer>
#     <security>
#       <authorization>
#         <remove users="*" />
#         <add accessType="Allow" roles="Administrators" />
#       </authorization>
#     </security>
#   </system.webServer>
# </configuration>