The find prototype in scripting/engine_v8.h in MongoDB 2.4.0 through 2.4.4 allows remote authenticated users to cause a denial of service (uninitialized pointer dereference and server crash) or possibly execute arbitrary code via an invalid RefDB object.
https://jira.mongodb.org/browse/SERVER-9878
http://www.openwall.com/lists/oss-security/2013/07/30/10
http://www.mongodb.org/about/alerts/
http://secunia.com/advisories/54170
http://blog.scrt.ch/2013/06/04/mongodb-rce-by-databasespraying/