StudioCMS has Authorization Bypass Through User-Controlled Key

Summary

StudioCMS contains a Broken Object Level Authorization (BOLA) vulnerability in the Content Management feature that allows users with the "Visitor" role to access draft content created by Editor/Admin/Owner users.

Details

The Issue: The endpoint /dashboard/content-management/edit?edit={UUID} validates user authentication but does NOT validate:

1. User role (should require Editor/Admin/Owner)
2. Content ownership (should verify the draft belongs to the user)

This allows users with "Visitor" role (lowest privilege) to access draft content created by Editor/Admin/Owner users by directly accessing the edit URL with the content UUID.

PoC

• User A: Editor role (example username: dummy04)
• User B: Visitor role (example username: dummy01)

Reproduction Steps:

Step 1 - Create draft as Editor:

1. Login as User A (Editor role)
2. Navigate to: http://localhost:4321/dashboard/content-management
3. Create new content (it will stay as draft)
4. After saving, note the UUID in the URL:

   http://localhost:4321/dashboard/content-management/edit?edit=bad87630-69a4-4cd6-bcb2-6965839dc148

Copy this UUID: bad87630-69a4-4cd6-bcb2-6965839dc148

Step 2 - Access draft as Visitor:

1. Login as Visitor and get auth_session cookie

curl -X POST "http://127.0.0.1:4321/studiocms_api/auth/login" -F 'username=dummy01' -F 'password=dummy01pass$'

<img width="1128" height="376" alt="01" src="https://github.com/user-attachments/assets/86c5290e-e7a2-470e-bbf5-5f5247eddec1" />

2. Proof of Visitor permission

   <img width="1899" height="450" alt="02" src="https://github.com/user-attachments/assets/aabd47d3-163f-4a56-8296-08bd40c5ccdc" />

3. Access Editor's draft using the UUID

curl "http://127.0.0.1:4321/dashboard/content-management/edit?edit=bad87630-69a4-4cd6-bcb2-6965839dc148" -H "Cookie: auth_session=qvawh6zv23hc2spu6xx7pzgrnn4rpd3q" -v

Result: Returns full HTML page with draft content (200 OK)

Impact

Impact Scenarios: