Detections
Analytics

Langflow < 1.9.1 Multiple Vulnerabilities

critical Nessus Plugin ID 326241

Synopsis

The remote host is affected by multiple vulnerabilities.

Description

The version of Langflow installed on the remote host is prior to 1.9.1. It is, therefore, affected by multiple vulnerabilities:

 - An Insecure Direct Object Reference (IDOR) vulnerability in the /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. (CVE-2026-55255)

 - Unauthenticated users can upload any amount of data to the server without any limitations, requiring only network access to Langflow. This can lead to space exhaustion on the server.
 In addition, the absolute path of the uploaded file is reported in the response, which is an information leak that can assist in chaining other attack primitives. (CVE-2026-55450)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Upgrade to Langflow version 1.9.1 or later.

See Also

http://www.nessus.org/u?52eb5616

http://www.nessus.org/u?ce119ea1

Plugin Details

Severity: Critical

ID: 326241

File Name: langflow_CVE-2026-55450.nasl

Version: 1.1

Type: Combined

Agent: windows, macosx, unix

Published: 7/10/2026

Updated: 7/10/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Critical

Score: 9.5

Percentile: 99.86

CVSS v2

Risk Factor: High

Base Score: 8.7

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:P

CVSS Score Source: CVE-2026-55255

CVSS v3

Risk Factor: Critical

Base Score: 9.9

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L

Vulnerability Information

CPE: cpe:/a:langflow:langflow

Required KB Items: installed_sw/Langflow

Patch Publication Date: 4/24/2026

Vulnerability Publication Date: 6/17/2026

Reference Information

CVE: CVE-2026-55255, CVE-2026-55450