# CVE-2026-18266: LangGenius Dify open redirect in AppInitializer OAuth flow

Source: https://junglewise.ai/threats/cve-2026-18266-langgenius-dify-open-redirect-in-appinitializer-oauth-flow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-29. Updated: 2026-07-29  
License: CC BY 4.0 with a link back

CVE-2026-18266 · Severity: medium · CVSS 5.4 · Published 2026-07-29

Dify, an open-source platform for building AI applications, is affected by a security flaw in how it handles user logins via third-party services (OAuth). An attacker could trick a user into clicking a malicious link that redirects them from the legitimate Dify site to a fraudulent website. This could be used to steal sensitive information or conduct phishing attacks against Dify users.

Technologies: [Langgenius Dify](https://junglewise.ai/threats/technologies/dify). Vendors: [Langgenius](https://junglewise.ai/threats/vendors/langgenius).

## Quick answers

**Is CVE-2026-18266 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-18266 being exploited in the wild.

**How severe is CVE-2026-18266?** Medium severity, with a CVSS score of 5.4, published 29 July 2026.

**Which products and versions are affected?** Langgenius Dify 1.11.4.

**Is there a fix for CVE-2026-18266?** A patch was published on 2026-07-29: Advisory updated with patch information Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-18266 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-18266?** Check whether you run Langgenius Dify at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An open redirect vulnerability (CWE-601) exists in the AppInitializer component of Dify during the OAuth flow handling. The application fails to properly validate the 'oauth_redirect_url' parameter, allowing an attacker to specify an arbitrary external URL. To exploit this, an attacker must entice a user to visit a specially crafted link. Successful exploitation allows the attacker to redirect the user's browser to a malicious site, potentially leading to the disclosure of sensitive information in the context of the application. A fix has been identified in the project's GitHub repository via pull request 38864.

## Affected products

- LangGenius Dify 1.11.4

## Timeline

- 2026-03-25: disclosed: Vulnerability reported to vendor
- 2026-07-23: advisory: Coordinated public release of advisory ZDI-26-452
- 2026-07-29: patched: Advisory updated with patch information

## References

- [https://www.zerodayinitiative.com/advisories/ZDI-26-452/](https://www.zerodayinitiative.com/advisories/ZDI-26-452/)

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