CVE-2026-33309: 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…

PriorityP270critical9.9CVSS 3.1

AVNACLPRLUINSCCHIHAH

EPSS

1.42%

69.4th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
langflow	langflow	>= 1.2.0 < 1.9.0	1.9.0
langflow	langflow	>= 1.2.0 < 1.9.0	1.9.0

CVSS provenance

nvdv3.19.9CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

ghsa7.1HIGH

osv7.1HIGH

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