# CVE-2026-3346: IBM Langflow Desktop stored XSS in Markdown rendering

Source: https://junglewise.ai/threats/cve-2026-3346-ibm-langflow-desktop-stored-xss-in-markdown-rendering  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-30. Updated: 2026-05-11  
License: CC BY 4.0 with a link back

CVE-2026-3346 · Severity: medium · CVSS 6.4 · Published 2026-04-30

IBM Langflow Desktop, a tool used for building and testing AI workflows, contains a security flaw that allows users to inject malicious scripts into the application's interface. An attacker with basic access could use this to steal login credentials or hijack the sessions of other users. This could lead to unauthorized access to sensitive AI models or corporate data managed within the platform.

Technologies: [IBM Langflow Desktop](https://junglewise.ai/threats/technologies/langflow-desktop). Vendors: [IBM](https://junglewise.ai/threats/vendors/ibm).

## Quick answers

**Is CVE-2026-3346 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-3346 being exploited in the wild.

**How severe is CVE-2026-3346?** Medium severity, with a CVSS score of 6.4, published 30 April 2026.

**Which products and versions are affected?** IBM Langflow Desktop 1.6.0 - 1.8.4.

**Is there a fix for CVE-2026-3346?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-3346 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-3346?** Check whether you run IBM Langflow Desktop 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

A stored cross-site scripting (XSS) vulnerability exists in IBM Langflow Desktop versions 1.6.0 through 1.8.4. The flaw is located in the Markdown rendering pipeline, specifically due to the unsafe use of 'rehypeRaw' without proper sanitization during event-streaming in the Playground component. An authenticated attacker can inject arbitrary HTML or JavaScript code that executes in the context of other users' browsers. This can be leveraged to disclose sensitive credentials or perform account takeover. While the advisory mentions CWE-89 (SQL Injection), the descriptive text and title explicitly confirm this is a stored XSS vulnerability. Users should upgrade to version 1.9.0 or newer to resolve the issue.

## Affected products

- IBM Langflow Desktop 1.6.0 - 1.8.4

## Timeline

- 2026-04-28: disclosed: Initial publication by IBM
- 2026-04-30: advisory: NVD publication date

## References

- [https://www.ibm.com/support/pages/node/7271095](https://www.ibm.com/support/pages/node/7271095)

## Related threats

- [IBM Langflow Desktop SSRF via DNS Rebinding](https://junglewise.ai/threats/cve-2026-3341-ibm-langflow-desktop-ssrf-via-dns-rebinding)
- [IBM Langflow Desktop code injection in code validation endpoint](https://junglewise.ai/threats/cve-2026-6543-ibm-langflow-desktop-code-injection-in-code-validation-endpoint)
- [IBM Langflow Desktop path traversal in API v2 file upload](https://junglewise.ai/threats/cve-2026-3345-ibm-langflow-desktop-path-traversal-in-api-v2-file-upload)
- [IBM Langflow Desktop IDOR in image download endpoint](https://junglewise.ai/threats/cve-2026-4503-ibm-langflow-desktop-idor-in-image-download-endpoint)
- [IBM Langflow Desktop path traversal in v2 API](https://junglewise.ai/threats/cve-2026-4502-ibm-langflow-desktop-path-traversal-in-v2-api)