CVE-2026-33309

critical · 9.9

Langflow is a tool for building and deploying AI-powered agents and workflows. Versions 1.2.0 through 1.8.1 have a bypass of the patch for CVE-2025-68478 (External Control of File Name), leading to the root architectural issue within `LocalStorageService` remaining unresolved. Because the underlying storage layer lacks boundary containment checks, the system relies entirely on the HTTP-layer `ValidatedFileName` dependency. This defense-in-depth failure leaves the `POST /api/v2/files/` endpoint vulnerable to Arbitrary File Write. The multipart upload filename bypasses the path-parameter guard, allowing authenticated attackers to write files anywhere on the host system, leading to Remote Code Execution (RCE). Version 1.9.0 contains an updated fix.

9.9

CVSS

11.1%

EPSS (exploit prob.)

96th

EPSS percentile

2026-03-24

Published

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Weaknesses

CWE-22CWE-73CWE-94CWE-284

Affected products

Vendor	Product	Affected versions
langflow	langflow	>= 1.2.0, < 1.9.0

Check a specific version with /api/v1/cve/match.

References

https://github.com/langflow-ai/langflow/security/advisories/GHSA-g2j9-7rj2-gm6c

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-33309