Amazon EMR Secret Agent creates a keytab file containing Kerberos credentials. This file is stored in the /tmp/ directory. A user with access to this directory and another account can potentially decrypt the keys and escalate to higher privileges. Users are advised to upgrade to Amazon EMR version 7.5 or higher. For Amazon EMR releases between 6.10 and 7.4, we strongly recommend that you run the bootstrap script and RPM files with the fix provided in the location below.
The storage of passwords in a recoverable format makes them subject to password reuse attacks by malicious users. In fact, it should be noted that recoverable encrypted passwords provide no significant benefit over plaintext passwords since they are subject not only to reuse by malicious attackers but also by malicious insiders. If a system administrator can recover a password directly, or use a brute force search on the available information, the administrator can use the password on other accounts.