# CVE-2026-33017: Langflow has Unauthenticated Remote Code Execution via Public Flow Build Endpoint

> CVE-2026-33017: Langflow has Unauthenticated Remote Code Execution via Public Flow Build Endpoint. CVSS 9.8 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2026-33017
Last updated: 2026-06-17T10:36:47Z

- Published: 2026-03-20 04:52 UTC · Updated: 2026-06-17 10:36 UTC · Assigner: GitHub\_M
- CVSS: 9.8 (CVSS 3.1) · Severity: Critical · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS: 96.2%, 100th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2026-03-25, federal due date 2026-04-08, ransomware use: Unknown
- CWE: CWE-306, CWE-94, CWE-95

## Description

Langflow is a tool for building and deploying AI-powered agents and workflows. In versions prior to 1.9.0, the POST /api/v1/build\_public\_tmp/{flow\_id}/flow endpoint allows building public flows without requiring authentication. When the optional data parameter is supplied, the endpoint uses attacker-controlled flow data (containing arbitrary Python code in node definitions) instead of the stored flow data from the database. This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution. This is distinct from CVE-2025-3248, which fixed /api/v1/validate/code by adding authentication. The build\_public\_tmp endpoint is designed to be unauthenticated (for public flows) but incorrectly accepts attacker-supplied flow data containing arbitrary executable code. This issue has been fixed in version 1.9.0.

## CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

## Affected vendors and products

- langflow-ai: langflow

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-33017)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-33017)
- [https://github.com/advisories/GHSA-rvqx-wpfh-mfx7](https://github.com/advisories/GHSA-rvqx-wpfh-mfx7)
- [https://github.com/langflow-ai/langflow/commit/73b6612e3ef25fdae0a752d75b0fabd47328d4f0](https://github.com/langflow-ai/langflow/commit/73b6612e3ef25fdae0a752d75b0fabd47328d4f0)
- [https://github.com/langflow-ai/langflow/security/advisories/GHSA-vwmf-pq79-vjvx](https://github.com/langflow-ai/langflow/security/advisories/GHSA-vwmf-pq79-vjvx)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-33017 · Markdown: https://rewindex.com/cve/CVE-2026-33017.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-33017 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:13:39.203Z