CVE-2025-71336Public exploitNetwork attack vector

Unauthenticated command execution via Custom MCP endpoint

Published Jun 25, 2026 · Updated Jun 25, 2026

OS command injection in Flowise before 3.0.6 allows remote attackers to execute arbitrary commands through the Custom MCP API endpoint. The /api/v1/node-load-method/customMCP handler launches the attacker-supplied command and arguments as a local MCP server without a sandbox. Default installations require no authentication unless credential environment variables are set, so compromise reaches the Flowise process, container, or server.

CVSS severity9.3
Critical
EPSS probability1.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in Flowise before 3.0.6 allows remote attackers to execute arbitrary commands through the Custom MCP API endpoint. The /api/v1/node-load-method/customMCP handler launches the attacker-supplied command and arguments as a local MCP server without a sandbox. Default installations require no authentication unless credential environment variables are set, so compromise reaches the Flowise process, container, or server.

The record

CVE
CVE-2025-71336
Published
Jun 25, 2026
Updated
Jun 25, 2026
Vendor
FlowiseAI
Product
Flowise
Classifications
CWE-78, T1190, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 25, 2026Record 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 <3.0.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FlowiseAI · Flowiseversion=0 <3.0.6

Published CVSS scores

9.8VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1190Exploit Public-Facing Application
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

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Your stack

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