Is CVE-2026-33309 actively exploited?

No active exploitation of CVE-2026-33309 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-33309 be exploited remotely?

Yes. CVE-2026-33309 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-33309?

CVE-2026-33309 has a CVSS score of 9.9 (CRITICAL).

HOME VULNERABILITIESCVE-2026-33309

CRITICAL

CVE-2026-33309

CWE-22Published: March 24, 2026· Updated: Mar 24, 2026

9.9

CVSS v3.1

EPSS:0.07%probability of exploitation in 30 daysPercentile:20.5th

Official 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.

NVD Source

Technical Analysis

CVE-2026-33309 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.9.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.