CVE-2025-41047 Overview
CVE-2025-41047 is a stored cross-site scripting (XSS) vulnerability in appRain CMF version 4.0.5. The flaw resides in the /apprain/developer/addons/update/ace endpoint. An authenticated attacker can inject malicious JavaScript through the data[Addon][layouts] and data[Addon][layouts_except] parameters. The application fails to validate or sanitize user input before persisting it. When another user loads the affected view, the injected script executes in their browser session under the application's origin.
Critical Impact
Authenticated attackers can persist arbitrary JavaScript that executes in the browsers of subsequent users visiting the affected addon interface, enabling session theft, credential harvesting, and administrative action hijacking.
Affected Products
- appRain CMF 4.0.5
- appRain developer addon module (/apprain/developer/addons/update/ace)
- Deployments exposing the developer addon interface to authenticated users
Discovery Timeline
- 2025-09-04 - CVE-2025-41047 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-41047
Vulnerability Analysis
The vulnerability is a stored XSS classified under [CWE-79]: Improper Neutralization of Input During Web Page Generation. The data[Addon][layouts] and data[Addon][layouts_except] POST parameters accept arbitrary content without HTML encoding or allowlist validation. The payload is stored server-side and rendered back to users of the addon administration interface. Because execution occurs in the context of authenticated sessions, an attacker can pivot from low-privileged access into broader administrative compromise if a higher-privileged user views the tainted content.
Exploitation requires an authenticated account with permission to submit addon update requests. User interaction is required for the payload to trigger, since a victim must load the affected view. The vulnerability does not directly grant code execution on the server, but scripts running in an administrator's browser can drive privileged operations exposed by the CMF.
Root Cause
The root cause is the absence of input validation and output encoding around the data[Addon][layouts] and data[Addon][layouts_except] parameters in the addon update handler. The application treats these parameters as trusted markup and reflects them into rendered HTML without contextual escaping. INCIBE-CERT documents this issue as part of a broader set of input handling weaknesses in appRain CMF 4.0.5. See the INCIBE Notice on Multiple Vulnerabilities for the coordinated advisory.
Attack Vector
The attack path is network-based and requires prior authentication. An attacker submits a crafted POST request to /apprain/developer/addons/update/ace containing a script payload inside the vulnerable parameters. The payload persists in the application data store. When any user with access to the addon view loads the page, their browser executes the attacker's JavaScript within the appRain origin. The attacker can then read session cookies, issue authenticated requests, or modify the DOM to phish credentials.
No verified public proof-of-concept is available. Refer to the INCIBE advisory linked above for coordinated disclosure details.
Detection Methods for CVE-2025-41047
Indicators of Compromise
- HTTP POST requests to /apprain/developer/addons/update/ace containing <script>, onerror=, onload=, or javascript: substrings in data[Addon][layouts] or data[Addon][layouts_except].
- Stored addon records whose layout fields contain HTML tags or JavaScript event handlers rather than plain layout identifiers.
- Unexpected outbound requests from administrator browsers to attacker-controlled domains shortly after viewing addon pages.
Detection Strategies
- Inspect web server and application logs for POST requests to the vulnerable endpoint with abnormally large or markup-bearing values in the affected parameters.
- Audit the addon data store for records where layouts or layouts_except fields deviate from expected identifier formats.
- Deploy a Content Security Policy in report-only mode and monitor violations originating from appRain administrative pages.
Monitoring Recommendations
- Alert on any authenticated write operation to /apprain/developer/addons/update/ace performed by non-developer accounts.
- Correlate administrator session activity with outbound HTTP requests to unknown domains generated from browser contexts.
- Track failed and successful authentication events for developer-tier accounts to identify credential misuse preceding exploitation.
How to Mitigate CVE-2025-41047
Immediate Actions Required
- Restrict access to /apprain/developer/addons/update/ace to trusted developer accounts and place the endpoint behind network segmentation where possible.
- Review existing addon records and remove any values in layouts or layouts_except that contain HTML or JavaScript syntax.
- Rotate session tokens and credentials for accounts that may have viewed compromised addon pages.
Patch Information
No vendor patch is referenced in the NVD entry at the time of publication. Monitor the INCIBE Notice on Multiple Vulnerabilities and the appRain project channels for a security release addressing CVE-2025-41047 and related issues in version 4.0.5.
Workarounds
- Enforce a strict Content Security Policy that disallows inline scripts on appRain administrative pages to blunt payload execution.
- Place the appRain application behind a web application firewall with rules that block script-like content in the data[Addon][layouts] and data[Addon][layouts_except] parameters.
- Limit developer role assignment to a minimal set of trusted users and require multi-factor authentication for those accounts.
- Temporarily disable the developer addon update interface if it is not actively used in production.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
