VYPR
Critical severityNVD Advisory· Published Mar 24, 2026· Updated Mar 25, 2026

Langflow has an Arbitrary File Write (RCE) via v2 API

CVE-2026-33309

Description

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 packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
langflowPyPI
>= 1.2.0, < 1.9.01.9.0

Affected products

1

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

3

News mentions

0

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