CVE-2025-41057 Overview
CVE-2025-41057 is a stored cross-site scripting (XSS) vulnerability in appRain CMF version 4.0.5. The flaw exists in the /apprain/developer/addons/update/rich_text_editor endpoint. Attackers can inject malicious JavaScript through the data[Addon][layouts] and data[Addon][layouts_except] parameters. The application fails to properly validate or sanitize user input before storing and rendering it.
Exploitation requires authenticated access with low privileges and user interaction. Successful attacks execute attacker-controlled scripts in the browsers of victims who visit affected pages. This can lead to session token theft, administrative action forgery, and content manipulation within the CMF interface.
Critical Impact
Authenticated attackers can persist malicious JavaScript in the appRain CMF that executes against other users, enabling session hijacking and unauthorized administrative operations.
Affected Products
- appRain CMF 4.0.5
- Deployments exposing the /apprain/developer/addons/update/rich_text_editor endpoint
- Instances allowing addon layout configuration by low-privileged authenticated users
Discovery Timeline
- 2025-09-04 - CVE-2025-41057 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-41057
Vulnerability Analysis
The vulnerability is a stored cross-site scripting flaw classified under [CWE-79], improper neutralization of input during web page generation. The affected component is the addon rich text editor update handler in appRain CMF 4.0.5. Two parameters, data[Addon][layouts] and data[Addon][layouts_except], accept attacker-controlled values without proper output encoding or input sanitization.
Because the payload is stored in the backend, every subsequent request that renders the affected view triggers execution of the injected script. The attack takes place over the network, requires low privileges, and needs a victim to load the affected page. Impact is limited to confidentiality and integrity of the browser context, but scoped effects reach other users of the CMF.
Root Cause
The root cause is missing input validation and output encoding in the addon update workflow. The application accepts arbitrary HTML and script content through the two parameters and later returns that content to authenticated users without contextual escaping. Framework-level protections such as HTML entity encoding or content security policy enforcement are not applied to the affected fields.
Attack Vector
An authenticated attacker with permission to update addons submits a crafted POST request to /apprain/developer/addons/update/rich_text_editor. The payload placed in data[Addon][layouts] or data[Addon][layouts_except] is persisted server-side. When another authenticated user, typically an administrator, browses to the addon configuration view, the browser parses and executes the stored JavaScript in the origin of the CMF, giving the attacker access to cookies, session state, and any actions the victim is authorized to perform.
No verified public proof-of-concept code is available. Refer to the INCIBE CERT Security Notice for the disclosure details.
Detection Methods for CVE-2025-41057
Indicators of Compromise
- POST requests to /apprain/developer/addons/update/rich_text_editor containing <script>, javascript:, or event handler substrings in data[Addon][layouts] or data[Addon][layouts_except].
- Unexpected HTML tags, encoded scripts, or external script references stored in the Addon records of the appRain database.
- Outbound browser requests from CMF administrators to unfamiliar domains shortly after loading addon management pages.
Detection Strategies
- Inspect web server access logs for requests to the vulnerable endpoint from accounts that do not normally perform addon maintenance.
- Deploy web application firewall (WAF) signatures that flag script tags and HTML event handlers in POST bodies targeting the addon update path.
- Query the addon configuration table for stored values containing angle brackets, onerror, onload, or base64-encoded script markers.
Monitoring Recommendations
- Alert on repeated writes to addon layout fields, especially outside standard change windows.
- Correlate authenticated session activity with anomalous outbound HTTP requests originating from administrator browsers.
- Retain HTTP request and response bodies for the /apprain/developer/ path hierarchy to enable retrospective hunting.
How to Mitigate CVE-2025-41057
Immediate Actions Required
- Restrict access to /apprain/developer/addons/update/rich_text_editor to trusted administrators using network or application-layer controls.
- Audit stored values in data[Addon][layouts] and data[Addon][layouts_except] and remove any content containing script or HTML markup.
- Rotate session tokens and administrative credentials if any injected content is discovered.
Patch Information
No vendor patch has been referenced in the enriched CVE data at the time of publication. Track the INCIBE CERT Security Notice for vendor updates and apply fixes as soon as they become available.
Workarounds
- Enforce a strict Content Security Policy that disallows inline scripts on appRain CMF pages.
- Add server-side input filtering that rejects HTML tags and JavaScript URIs in the affected parameters.
- Limit developer and addon management roles to a minimal set of accounts protected by multi-factor authentication.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
