CVE-2026-33017

CRITICAL KEV

Langflow has Unauthenticated Remote Code Execution via Public Flow Build Endpoint

Title source: cna

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.

Exploits (7)

nomisec WORKING POC 1 stars
by omer-efe-curkus · remote
https://github.com/omer-efe-curkus/CVE-2026-33017-Langflow-RCE-PoC
nomisec WORKING POC
by SimoesCTT · remote
https://github.com/SimoesCTT/Sovereign-Echo-33017
nomisec WORKING POC
by MaxMnMl · remote
https://github.com/MaxMnMl/langflow-CVE-2026-33017-poc

Scores

CVSS v3 9.8
EPSS 0.0565
EPSS Percentile 90.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CISA KEV 2026-03-25
VulnCheck KEV 2026-03-19
ENISA EUVD EUVD-2026-13556
CWE
CWE-306 CWE-94 CWE-95
Status published
Products (4)
langflow/langflow 1.9.0 dev0 (12 CPE variants)
langflow/langflow < 1.8.2
langflow-ai/langflow < 1.9.0
pypi/langflow 0 - 1.8.2PyPI
Published Mar 20, 2026
KEV Added Mar 25, 2026
Tracked Since Mar 20, 2026