CVE-2025-43854: Langgenius Dify CSRF Vulnerability

CVE-2025-43854 Overview

CVE-2025-43854 is a clickjacking vulnerability affecting Dify, an open-source large language model (LLM) application development platform maintained by Langgenius. The default deployment configuration prior to version 1.3.0 fails to set appropriate frame-protection response headers. Attackers can embed the Dify interface within an attacker-controlled page and trick authenticated users into performing unintended actions. The issue is tracked as CWE-1021: Improper Restriction of Rendered UI Layers or Frames and was resolved in Dify 1.3.0.

Critical Impact
Authenticated Dify users can be coerced into executing unauthorized UI actions when they visit a malicious page that frames the Dify application, exposing account data and configuration to compromise.

Affected Products

Langgenius Dify versions prior to 1.3.0
Dify deployments running on Node.js distributions
Self-hosted Dify instances using default configuration

Discovery Timeline

2025-04-28 - CVE-2025-43854 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-43854

Vulnerability Analysis

The vulnerability exists because the default Dify web application does not enforce anti-framing controls on its HTTP responses. Without a Content-Security-Policy: frame-ancestors directive or an X-Frame-Options header, browsers permit any origin to render Dify pages inside an <iframe>. An attacker hosts a page that embeds the victim's authenticated Dify session and overlays deceptive UI elements. When the victim interacts with the visible decoy, the clicks are delivered to the hidden Dify interface. This transforms trusted UI actions such as workflow modifications, API key generation, or dataset deletion into attacker-controlled operations.

Root Cause

The root cause is the absence of frame-busting response headers in the default deployment. Modern browsers require explicit server-side directives to prevent third-party framing. The Dify default configuration shipped without these directives, leaving all rendered routes exposed to UI redress attacks. The fix introduced in pull request #18516 applies restrictive frame-ancestors policies to the application responses.

Attack Vector

Exploitation requires the victim to visit an attacker-controlled web page while holding an active Dify session. The attacker crafts an HTML page that loads the Dify origin inside an invisible or opacity-zero iframe. Overlay elements guide the victim's cursor to click on sensitive Dify controls without the user perceiving the underlying application. The attack is network-reachable, requires user interaction, and does not need credentials on the attacker's side because it abuses the victim's existing authentication cookies.

No verified public exploit code is available. Refer to the GitHub Security Advisory GHSA-jhgq-cx3f-vj5p for additional technical context.

Detection Methods for CVE-2025-43854

Indicators of Compromise

Referer headers on Dify requests originating from unexpected external domains
Sudden configuration or workflow changes performed by authenticated users without corresponding session activity in the UI
Browser telemetry showing Dify pages loaded within third-party iframes
Access logs showing sensitive endpoints invoked shortly after users visited untrusted external sites

Detection Strategies

Inspect Dify HTTP responses to confirm presence of X-Frame-Options or Content-Security-Policy: frame-ancestors directives
Correlate authentication events with Referer values pointing to unknown origins
Deploy web application firewall rules that flag requests missing expected origin headers
Review browser-side content security policy violation reports if reporting endpoints are configured

Monitoring Recommendations

Enable audit logging for privileged Dify actions such as API key creation, model deletion, and dataset export
Monitor for anomalous request patterns from authenticated sessions occurring within seconds of external navigation
Track Dify version metadata across deployments to identify instances still running builds prior to 1.3.0

How to Mitigate CVE-2025-43854

Immediate Actions Required

Upgrade all Dify installations to version 1.3.0 or later
Audit exposed Dify endpoints to confirm frame-protection headers are returned on every route
Rotate API keys and session tokens for accounts that may have interacted with untrusted external pages
Review recent administrative actions in Dify audit logs for unauthorized changes

Patch Information

The fix is delivered in Dify 1.3.0 via pull request #18516. The patch adds server-side frame-ancestors enforcement to the default configuration. Full remediation details are documented in the GitHub Security Advisory GHSA-jhgq-cx3f-vj5p.

Workarounds

Place Dify behind a reverse proxy that injects X-Frame-Options: DENY on all responses
Add a Content-Security-Policy: frame-ancestors 'none' header at the load balancer or ingress layer
Restrict Dify access to trusted network segments until the upgrade is applied
Instruct administrators to use dedicated browser profiles when managing Dify to reduce cross-site session exposure

bash

# Example nginx configuration to enforce frame protection
add_header X-Frame-Options "DENY" always;
add_header Content-Security-Policy "frame-ancestors 'none'" always;