CVE-2025-62421 Overview
CVE-2025-62421 is a stored cross-site scripting (XSS) vulnerability in DataEase, an open-source data visualization and analytics platform. The flaw affects all versions through 2.10.13 and stems from improper file upload validation combined with an authentication bypass in the StaticResourceApi interface. Attackers can upload HTML files containing malicious JavaScript by exploiting a permissive URL allowlist check in the TokenFilter. The vulnerability is tracked under CWE-79 and fixed in version 2.10.14.
Critical Impact
Unauthenticated attackers can upload malicious HTML files that execute arbitrary JavaScript in the browser context of DataEase users, enabling session theft and account takeover.
Affected Products
- DataEase versions up to and including 2.10.13
- DataEase self-hosted deployments exposing the StaticResourceApi
- DataEase instances accessible over the network without upstream WAF filtering
Discovery Timeline
- 2025-10-17 - CVE-2025-62421 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-62421
Vulnerability Analysis
The vulnerability exists in the StaticResourceApi interface, which defines an upload/{fileId} route. This route uses a URL path parameter where users control both the filename and extension of uploaded files. During request handling, the TokenFilter calls the WhitelistUtils#match method to check whether the URL path belongs to an authentication allowlist.
The allowlist logic checks the request URI suffix. If the URI ends with .js or similar static asset extensions, the filter treats the request as safe and skips permission checks. An attacker can request upload/1.js while specifying an arbitrary file extension in the uploaded content, bypassing authentication entirely.
Because the uploaded file is served back through the same static resource endpoint, the attacker can host HTML files containing JavaScript payloads. When a victim visits the crafted URL, the payload executes in the DataEase origin context.
Root Cause
The root cause is a mismatch between the routing logic and the authentication filter. The WhitelistUtils#match method inspects only the URI suffix without validating the true resource type or the request handler. This design flaw allows attackers to disguise sensitive upload endpoints as static asset requests. Missing content-type validation on the upload handler further compounds the issue by permitting HTML content under a .js request path.
Attack Vector
Exploitation requires only network access to the DataEase instance. The attacker crafts an HTTP request to upload/1.js and submits a file whose actual filename ends with .html or contains executable script markup. The server accepts the file without authentication because the URI matches the static asset allowlist. The attacker then distributes a link to the uploaded resource. When authenticated DataEase users open the link, the malicious JavaScript runs with their session cookies and privileges. No verified public exploit code is available at this time.
Detection Methods for CVE-2025-62421
Indicators of Compromise
- HTTP requests to paths matching upload/*.js where the response or stored artifact contains HTML or script content
- Unexpected files with .html, .htm, or .svg extensions in DataEase static resource directories
- Outbound requests from user browsers to attacker-controlled domains after visiting DataEase URLs
- Access logs showing upload requests to StaticResourceApi without preceding authentication tokens
Detection Strategies
- Inspect web server access logs for POST or PUT requests to upload/{fileId} endpoints where the URI ends in .js but the uploaded payload is not JavaScript
- Scan the DataEase file storage directory for files whose extensions do not match declared MIME types
- Deploy WAF rules that block file uploads containing <script>, <iframe>, or event handler attributes
- Correlate anomalous file upload activity with subsequent user session anomalies
Monitoring Recommendations
- Enable verbose logging on the TokenFilter and StaticResourceApi components to capture allowlist matches
- Monitor DataEase administrator and analyst session activity for unexpected API calls following link clicks
- Alert on any static resource that returns a text/html content type from a .js URL path
How to Mitigate CVE-2025-62421
Immediate Actions Required
- Upgrade DataEase to version 2.10.14 or later, which contains the official fix
- Audit the upload/ directory and remove any suspicious HTML, SVG, or script files uploaded by untrusted users
- Rotate session tokens and API keys for all DataEase users who may have visited attacker-supplied links
- Restrict network access to DataEase management endpoints using an upstream reverse proxy or firewall
Patch Information
The DataEase maintainers released version 2.10.14 to address CVE-2025-62421. The fix is documented in the DataEase GitHub Security Advisory GHSA-2wmv-rr3p-pf43. The patch corrects the WhitelistUtils#match logic so that upload routes are no longer treated as static assets based on URI suffix alone.
Workarounds
- No official workarounds exist according to the vendor advisory; upgrading is the only supported remediation
- As a temporary compensating control, block external access to upload/*.js paths at a reverse proxy until the patch is applied
- Enforce strict Content Security Policy (CSP) headers to reduce the impact of successful script injection
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
