CVE-2025-40662: DM Corporative CMS Path Disclosure Flaw

CVE-2025-40662 Overview

CVE-2025-40662 is an absolute path disclosure vulnerability affecting DM Corporative CMS by ACC. The flaw allows an unauthenticated remote attacker to retrieve the absolute filesystem path of webroot content by requesting a non-existent file. The server responds with verbose error output that reveals internal directory structure and file locations. This information helps attackers map the application, target follow-on attacks, and chain with other weaknesses. The issue is tracked under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor).

Critical Impact

Unauthenticated remote attackers can disclose absolute server paths and reconnaissance data by requesting non-existent webroot files, enabling targeted follow-on attacks.

Affected Products

• ACC DM Corporative CMS (all versions listed in the CPE: cpe:2.3:a:acc:dm_corporative_cms:*:*:*:*:*:*:*:*)
• Web deployments served from the affected CMS webroot
• Installations exposed to untrusted networks

Discovery Timeline

• 2025-06-10 - CVE-2025-40662 published to the National Vulnerability Database
• 2025-10-22 - Last updated in NVD database

Technical Details for CVE-2025-40662

Vulnerability Analysis

The vulnerability is an information disclosure flaw in DM Corporative CMS. When a client requests a resource under the webroot that does not exist, the application returns a response that reveals the absolute filesystem path of the requested file. This behavior exposes server-side directory layouts to any unauthenticated remote user.

The attack vector is network-based and requires no privileges or user interaction. Attackers can automate scans against many endpoints and harvest path data across deployments. The disclosed paths typically include directory names that reveal the operating system, web server configuration, application install directory, and account naming conventions. See the INCIBE Security Notice for vendor coordination details.

Root Cause

The root cause is improper error handling in the CMS request pipeline. When the application cannot resolve a requested file under the webroot, the resulting error message embeds the absolute path rather than returning a generic HTTP 404 response. Verbose error output is enabled in the default configuration, so production deployments expose internal paths unless the operator manually suppresses error detail.

Attack Vector

An unauthenticated attacker sends a crafted HTTP request to any non-existent file path under the application webroot. The server responds with an error page or error string that contains the absolute path of the resolved location. No authentication, no special header, and no client-side interaction is required. Attackers commonly combine this disclosure with path traversal, local file inclusion, or upload bugs that need exact target paths to succeed.

The vulnerability does not, on its own, allow code execution or data modification. Its value is reconnaissance: it accelerates and refines other intrusions against the same host.

Detection Methods for CVE-2025-40662

Indicators of Compromise

• HTTP requests targeting random or unusual non-existent paths under the CMS webroot, often in rapid sequence from a single source.
• Server access logs showing 404 or 500 responses correlated with response bodies containing absolute filesystem paths.
• Outbound responses including strings such as /var/www/, C:\inetpub\, or other server-internal directory prefixes.

Detection Strategies

• Inspect web server logs for spikes in 404 responses tied to oddly named or fuzzed file requests.
• Deploy web application firewall rules that flag response bodies containing absolute path patterns.
• Run authenticated vulnerability scans against DM Corporative CMS hosts to confirm presence of the verbose error response.

Monitoring Recommendations

• Forward web server and CMS error logs into a centralized logging or SIEM platform for pattern-based alerting.
• Alert on response payloads containing filesystem path prefixes that should never leave the server.
• Track repeated probing from individual source IPs and correlate with subsequent exploitation attempts.

How to Mitigate CVE-2025-40662

Immediate Actions Required

• Contact ACC and apply the security update for DM Corporative CMS as soon as it is available, following the guidance in the INCIBE Security Notice.
• Disable verbose error reporting in the CMS and underlying web server configuration for production environments.
• Restrict administrative and management interfaces to trusted networks only.

Patch Information

At the time of writing, no vendor advisory URLs or fixed version identifiers were published in the NVD entry. Operators should monitor ACC vendor channels and the linked INCIBE bulletin for patched releases of DM Corporative CMS and apply them promptly when available.

Workarounds

• Configure the web server to return a generic custom 404 page that does not include server-side path or stack information.
• Add a web application firewall rule to strip or block responses containing absolute filesystem paths.
• Limit external exposure of the CMS by placing it behind authenticated reverse proxies or IP allowlists where feasible.

# Configuration example: suppress verbose error output on common web servers

# Apache - in httpd.conf or vhost
ServerSignature Off
ServerTokens Prod
ErrorDocument 404 /errors/404.html
ErrorDocument 500 /errors/500.html

# Nginx - in server block
server_tokens off;
error_page 404 /errors/404.html;
error_page 500 502 503 504 /errors/50x.html;