In Apache Hadoop versions 2.6.1 to 2.6.5, 2.7.0 to 2.7.3, and 3.0.0-alpha1, if a file in an encryption zone with access permissions that make it world readable is localized via YARN's localization mechanism, that file will be stored in a world-readable location and can be shared freely with any application that requests to localize that file.
The YARN NodeManager in Apache Hadoop 2.6.x before 2.6.5 and 2.7.x before 2.7.3 can leak the password for credential store provider used by the NodeManager to YARN Applications.
HDFS clients interact with a servlet on the DataNode to browse the HDFS namespace. The NameNode is provided as a query parameter that is not validated in Apache Hadoop before 2.7.0.
In Apache Hadoop 2.6.x before 2.6.5 and 2.7.x before 2.7.3, a remote user who can authenticate with the HDFS NameNode can possibly run arbitrary commands with the same privileges as the HDFS service.
Apache Hadoop 2.6.x encrypts intermediate data generated by a MapReduce job and stores it along with the encryption key in a credentials file on disk when the Intermediate data encryption feature is enabled, which allows local users to obtain sensitive information by reading the file.