CVE-2019-17426

Automattic Mongoose through 5.7.4 allows attackers to bypass access control (in some applications) because any query object with a _bsontype attribute is ignored. For example, adding "_bsontype":"a" can sometimes interfere with a query filter. NOTE: this CVE is about Mongoose’s failure to work around this _bsontype special case that exists in older versions of the bson parser (aka the mongodb/js-bson project).

Source: CVE-2019-17426