Package Instance

Improper Authentication
In all versions of Apache Spark, the standalone resource manager accepts code to execute on a `master` host, that then runs that code on `worker` hosts. The master itself does not, by design, execute user code. A specially-crafted request to the master can, however, cause the master to execute code too. Note that this does not affect standalone clusters with authentication enabled. While the master host typically has less outbound access to other resources than a worker, the execution of code on the master is nevertheless unexpected.

Improper Authentication
Apache Spark standalone master exposes a REST API for job submission, in addition to the submission mechanism used by spark-submit. In standalone, the config property `spark.authenticate.secret` establishes a shared secret for authenticating requests to submit jobs via spark-submit. However, the REST API does not use this or any other authentication mechanism, and this is not adequately documented. In this case, a user would be able to run a driver program without authenticating, but not launch executors, using the REST API.

Information Exposure
In Apache Spark it is possible for a malicious user to construct a URL pointing to a Spark cluster UI job and stage info pages, and if a user can be tricked into accessing the URL, can be used to cause script to execute and expose information from the user view of the Spark UI. While some browsers like recent versions of Chrome and Safari are able to block this type of attack, current versions of Firefox (and possibly others) do not.