NoSQL Injection in loopback-connector-mongodb
Versions of `loopback-connector-mongodb` before 3.6.0 are vulnerable to NoSQL injection.
MongoDB Connector for LoopBack fails to properly sanitize a filter passed to query the database by allowing the dangerous `$where` property to be passed to the MongoDB Driver. The Driver allows the special `$where` property in a filter to execute JavaScript (client can pass in a malicious script) on the database Driver. This is an intended feature of MongoDB
https://docs.mongodb.com/manual/core/server-side-javascript/ unless disabled (instructions here
https://docs.mongodb.com/manual/core/server-side-javascript/#disable-server-side-js)
A proof of concept malicious query:
```
GET /POST filter={"where": {"$where": "function(){sleep(5000); return this.title.contains('Hello');}"}}
```
The above makes the database sleep for 5 seconds and then returns all “Posts” with the title containing the word `Hello`.
## Recommendation
Update to version 3.6.0 or later.