CVE-2025-8943

CRITICAL EXPLOITED NUCLEI

Flowise < 3.0.1 - Unauthenticated Remote Code Execution via Custom MCPs Feature

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2025-8943 has been observed exploited in the wild (reported by VulnCheck KEV). EIP tracks 1 public exploit from researchers including Assaf Levkovich, including a Metasploit module exploits/multi/http/flowise_custommcp_rce. A Nuclei detection template is also available.

AI-analyzed exploit summary This Metasploit module exploits a remote code execution vulnerability in Flowise via the customMCP endpoint, allowing arbitrary command execution through the StdioClientTransport mechanism. It supports both authenticated and unauthenticated exploitation depending on Flowise configuration.

Description

The Custom MCPs feature is designed to execute OS commands, for instance, using tools like `npx` to spin up local MCP Servers. However, Flowise's inherent authentication and authorization model is minimal and lacks role-based access controls (RBAC). Furthermore, in Flowise versions before 3.0.1 the default installation operates without authentication unless explicitly configured. This combination allows unauthenticated network attackers to execute unsandboxed OS commands.

Exploits (1)

metasploit WORKING POC EXCELLENT
by Assaf Levkovich · rubypocwin
https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/multi/http/flowise_custommcp_rce.rb

This Metasploit module exploits a remote code execution vulnerability in Flowise via the customMCP endpoint, allowing arbitrary command execution through the StdioClientTransport mechanism. It supports both authenticated and unauthenticated exploitation depending on Flowise configuration.

Classification
Working Poc 100%
Attack Type
Rce
Complexity
Trivial
Reliability
Reliable
Target: Flowise versions >= 2.2.7-patch.1 and < 3.0.1
No auth needed
Prerequisites: Network access to Flowise API (port 3000 by default) · Flowise version within vulnerable range
devstral-2 · analyzed Feb 16, 2026 Full analysis →

Nuclei Templates (1)

Flowise < 3.0.1 - Remote Command Execution
CRITICALVERIFIEDby zezezez
Shodan: http.title:"Flowise"

References (1)

Core 1

Scores

CVSS v3 9.8
EPSS 0.8647
EPSS Percentile 99.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact total

Details

VulnCheck KEV 2025-11-27
CWE
CWE-862 CWE-306
Status published
Products (2)
flowiseai/flowise < 3.0.1
npm/flowise 0npm
Published Aug 14, 2025
Tracked Since Feb 18, 2026