CVE-2025-8943Public exploitNetwork attack vector

Unauthenticated code execution via Custom MCP commands

Published Aug 14, 2025 · Updated Aug 18, 2025

OS command injection in the Custom MCP endpoint in Flowise before 3.0.1 allows remote attackers to execute commands without authentication. The node-load-method/customMCP endpoint passes attacker-controlled command and args values to an unsandboxed MCP process launcher. Default deployments lack authentication, so network reachability is sufficient for code execution with the privileges of the Flowise process.

CVSS severity9.8
Critical
EPSS probability66.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

OS command injection in the Custom MCP endpoint in Flowise before 3.0.1 allows remote attackers to execute commands without authentication. The node-load-method/customMCP endpoint passes attacker-controlled command and args values to an unsandboxed MCP process launcher. Default deployments lack authentication, so network reachability is sufficient for code execution with the privileges of the Flowise process.

The record

CVE
CVE-2025-8943
Published
Aug 14, 2025
Updated
Aug 18, 2025
Vendor
FlowiseAI
Product
Flowise
Classifications
CWE-306, CWE-78, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 14, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <3.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FlowiseAI · Flowiseversion=0 <3.0.1

Published CVSS scores

9.8GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo