CVE-2026-91931Network attack vectorHinoki check available

Authenticated code execution via attacker-controlled npx packages

Published Sep 15, 2026 · Updated Sep 15, 2026

Remote code execution in Flowise before 3.1.4 allows remote authenticated users to run code through crafted Custom MCP npx package names. The Custom MCP node passes attacker-controlled package names from mcpServerConfig to npx, causing npm package code to execute on the server. An authenticated account with Custom MCP configuration access is required, and successful exploitation compromises the application under Flowise's service privileges.

CVSS severityUnavailable
Unscored
EPSS probability0.63%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Remote code execution in Flowise before 3.1.4 allows remote authenticated users to run code through crafted Custom MCP npx package names. The Custom MCP node passes attacker-controlled package names from mcpServerConfig to npx, causing npm package code to execute on the server. An authenticated account with Custom MCP configuration access is required, and successful exploitation compromises the application under Flowise's service privileges.

The record

CVE
CVE-2026-91931
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
FlowiseAI
Product
Flowise
Classifications
T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=0 <3.1.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

FlowiseAI · Flowiseversion=0 <3.1.4

Published CVSS scores

No CVSS assessment is available in this record.

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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

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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