CVE-2026-21445

Langflow Unchained: Open Gates and Path Traversals in the AI Pipeline

Amit Schendel
Amit Schendel
Senior Security Researcher

Jan 2, 2026·6 min read·10 visits

Executive Summary (TL;DR)

The Langflow dev team forgot to lock the front door. Critical API endpoints—including log streams and user creation—lacked authentication checks. Combined with a path traversal vulnerability in the profile picture handler, unauthenticated attackers could fully compromise the instance, steal OpenAI/Anthropic keys, and exfiltrate server files.

Langflow, a popular visual framework for building AI agents, shipped with critical endpoints completely exposed to unauthenticated users. This vulnerability allowed attackers to stream live application logs (leaking API keys), create administrative users, and read arbitrary files via directory traversal.

Fix Analysis (1)

Technical Appendix

CVSS Score
8.8/ 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P

Affected Systems

Langflow AI Agent Builder

Affected Versions Detail

Product
Affected Versions
Fixed Version
Langflow
langflow-ai
< 1.7.0.dev451.7.0.dev45
AttributeDetail
CWE IDCWE-306 (Missing Authentication)
Secondary CWECWE-22 (Path Traversal)
CVSS v4.08.8 (High)
Attack VectorNetwork
Privileges RequiredNone
ImpactCritical (Data Leakage, RCE potential)
CWE-306
Missing Authentication for Critical Function

The software does not prove that a claim of identity is correct when that claim is used to execute a critical function.

Vulnerability Timeline

Vulnerability Published and Patched
2026-01-02