CVE-2025-63388: Langgenius Dify Auth Bypass Vulnerability

CVE-2025-63388 Overview

A Cross-Origin Resource Sharing (CORS) misconfiguration vulnerability exists in Dify v1.9.1 within the /console/api/system-features endpoint. The vulnerability stems from an overly permissive CORS policy that reflects arbitrary Origin headers and sets Access-Control-Allow-Credentials: true, allowing any external domain to make authenticated cross-origin requests. This configuration flaw can enable attackers to bypass same-origin policy protections and potentially access sensitive data or perform actions on behalf of authenticated users.

Critical Impact

This vulnerability allows any external domain to make authenticated cross-origin requests, potentially enabling data theft or unauthorized actions on behalf of legitimate users through malicious websites.

Affected Products

• Langgenius Dify v1.9.1
• Langgenius Dify Node.js deployments

Discovery Timeline

• 2025-12-18 - CVE-2025-63388 published to NVD
• 2026-01-28 - Last updated in NVD database

Technical Details for CVE-2025-63388

Vulnerability Analysis

This CORS misconfiguration vulnerability occurs when the Dify application's /console/api/system-features endpoint reflects arbitrary Origin headers in its CORS response without proper validation. When combined with the Access-Control-Allow-Credentials: true header, browsers will include cookies and other authentication credentials with cross-origin requests from any domain.

The vulnerability allows an attacker to craft a malicious website that, when visited by an authenticated Dify user, can make requests to the vulnerable endpoint and read the response data. This effectively bypasses the browser's same-origin policy, which is designed to prevent such cross-domain data access.

Note: The supplier (Langgenius) disputes this vulnerability, stating that "sending requests with credentials does not provide any additional access compared to unauthenticated requests."

Root Cause

The root cause is improper implementation of CORS headers in the /console/api/system-features endpoint. Rather than implementing a whitelist of trusted origins or blocking credential-bearing requests from untrusted origins, the application reflects the incoming Origin header value directly in the Access-Control-Allow-Origin response header while simultaneously enabling credential sharing.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction beyond visiting a malicious website. An attacker can exploit this vulnerability by:

1. Creating a malicious webpage that contains JavaScript code to make cross-origin requests to the vulnerable Dify endpoint
2. Enticing an authenticated Dify user to visit the malicious page
3. The browser automatically includes the user's session cookies with the request due to Access-Control-Allow-Credentials: true
4. The attacker's JavaScript can then read the response data, potentially exposing sensitive system configuration information

Technical details and proof-of-concept examples are available in the GitHub Gist PoC Code and GitHub Gist Payload Example.

Detection Methods for CVE-2025-63388

Indicators of Compromise

• Unusual cross-origin requests to /console/api/system-features from unexpected referrer domains
• Web application logs showing requests with Origin headers from untrusted or unknown domains
• Anomalous access patterns to system configuration endpoints from authenticated sessions

Detection Strategies

• Monitor web server access logs for requests to /console/api/system-features with suspicious or unknown Origin headers
• Implement Content Security Policy (CSP) reporting to detect unauthorized cross-origin resource loading attempts
• Deploy web application firewall (WAF) rules to flag requests with mismatched Origin and Referer headers
• Audit CORS response headers in application responses to identify overly permissive configurations

Monitoring Recommendations

• Enable detailed logging for all API endpoints, particularly those returning sensitive system information
• Set up alerts for unusual patterns of cross-origin requests to authenticated endpoints
• Regularly audit CORS configurations across all API endpoints using automated security scanning tools

How to Mitigate CVE-2025-63388

Immediate Actions Required

• Review and restrict the CORS configuration for the /console/api/system-features endpoint to allow only trusted origins
• Implement an explicit allowlist of permitted origins rather than reflecting arbitrary Origin headers
• Consider removing Access-Control-Allow-Credentials: true unless absolutely necessary for legitimate cross-origin functionality
• Monitor the Dify GitHub Discussions for vendor updates and patches

Patch Information

No official patch has been released at this time. The vendor (Langgenius) disputes the severity of this vulnerability. Users should monitor the Dify GitHub Discussions for any future security updates or configuration guidance.

Workarounds

• Configure a reverse proxy (such as nginx or Apache) to override CORS headers and implement a proper origin allowlist
• Use network-level controls to restrict access to the Dify console API from trusted networks only
• Implement additional authentication layers such as IP whitelisting for administrative endpoints
• Deploy a Web Application Firewall (WAF) to filter requests with untrusted Origin headers

# Example nginx configuration to restrict CORS origins
# Add to your nginx server block for the Dify application

location /console/api/system-features {
    # Only allow specific trusted origins
    set $cors_origin "";
    if ($http_origin ~* "^https://(trusted-domain\.com|another-trusted\.org)$") {
        set $cors_origin $http_origin;
    }
    
    add_header 'Access-Control-Allow-Origin' $cors_origin always;
    add_header 'Access-Control-Allow-Credentials' 'true' always;
    add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS' always;
    
    proxy_pass http://dify_backend;
}