CVE-2025-32373 Overview
CVE-2025-32373 is an authorization flaw in DNN Platform (formerly DotNetNuke), an open-source content management system built on the Microsoft .NET stack. In specific configurations, authenticated users can craft requests to enumerate and access portal files that fall outside their intended permissions. The weakness is tracked as [CWE-639: Authorization Bypass Through User-Controlled Key]. DNN maintainers resolved the issue in version 9.13.8. The vulnerability affects confidentiality only, with no direct impact to integrity or availability. Administrators running multi-portal DNN installations with registered user accounts are the primary population at risk.
Critical Impact
Authenticated DNN users can enumerate and read portal files beyond their authorized scope, exposing content intended only for other portals or privileged roles.
Affected Products
- DNN Platform (DotNetNuke) versions prior to 9.13.8
- dnnsoftware/Dnn.Platform source distributions in limited configurations
- Hosted DNN portals that permit user registration
Discovery Timeline
- 2025-04-09 - CVE-2025-32373 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-32373
Vulnerability Analysis
The flaw is an insecure direct object reference (IDOR) in the DNN portal file subsystem. A registered user can submit a request that references a portal file identifier or path outside their authorized scope. The server honors the request without fully validating that the caller's portal context matches the requested resource. This produces an authorization bypass restricted to file read and enumeration operations.
Exploitation requires valid credentials, since the attack surface is only reachable by authenticated accounts. On DNN sites that allow self-registration, the barrier to obtaining those credentials is minimal. Successful exploitation yields disclosure of portal files that may contain uploaded documents, draft content, or configuration artifacts stored under portal directories.
The issue does not permit file modification, deletion, or code execution. Impact is bounded to information disclosure, consistent with the CVSS confidentiality-only impact profile. The EPSS score of 0.377% reflects limited observed exploitation attempts in the wild.
Root Cause
The root cause is missing or incomplete authorization enforcement on portal file access handlers. The application uses a user-controlled key, such as a file identifier or path parameter, to locate the requested resource. It fails to verify that the resource belongs to a portal the caller may access. This pattern matches [CWE-639] directly.
Attack Vector
The attack is network-reachable over HTTP or HTTPS and requires low privileges in the form of any registered account. No user interaction is required. The attacker crafts requests to DNN portal file endpoints and manipulates identifiers to enumerate or retrieve files from other portals or restricted paths. See the DNN GitHub Security Advisory GHSA-vxcm-4rwh-chpc for maintainer-provided technical context.
Detection Methods for CVE-2025-32373
Indicators of Compromise
- Authenticated HTTP requests from a single session iterating sequential file or folder identifiers against DNN portal file handlers.
- Access log entries showing a non-admin user retrieving files whose portal ID does not match the user's assigned portal.
- Spikes in 200 OK responses to portal file endpoints originating from recently registered accounts.
Detection Strategies
- Correlate IIS or reverse-proxy logs with DNN audit events to flag file access that crosses portal boundaries.
- Alert on registered-user accounts issuing high-volume requests to file download or metadata endpoints within a short window.
- Review DNN event logs for repeated access denials followed by successful retrieval of adjacent identifiers.
Monitoring Recommendations
- Forward IIS, DNN application, and database logs to a centralized analytics platform for cross-source correlation.
- Baseline normal per-role file access volume so enumeration bursts stand out against routine activity.
- Monitor newly created accounts for early access patterns targeting file endpoints within minutes of registration.
How to Mitigate CVE-2025-32373
Immediate Actions Required
- Upgrade DNN Platform to version 9.13.8 or later across every production and staging portal.
- Audit registered user accounts and disable or purge accounts that are inactive or unverified.
- Review portal file directories for sensitive content that should be relocated or access-restricted independent of application logic.
Patch Information
DNN maintainers fixed the authorization check in release 9.13.8. Administrators should apply the official upgrade package following the DNN GitHub Security Advisory GHSA-vxcm-4rwh-chpc. Validate upgrades in a staging environment and verify portal file access controls behave as expected post-upgrade.
Workarounds
- Disable public user registration until the patch is deployed to reduce the pool of accounts that can reach the vulnerable endpoints.
- Restrict access to portal file paths at the web server or reverse proxy layer using IP allowlists for trusted administrators.
- Move sensitive uploads out of DNN-managed portal directories into storage with independent access control enforcement.
# Configuration example: block anonymous registration pending patch
# web.config snippet (DNN host settings should also be reviewed in the UI)
<add key="UserRegistration" value="None" />
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
