Use of Hard-coded Credentials in Apache Kylin

Apache Kylin provides encryption classes PasswordPlaceholderConfigurer to help users encrypt their passwords. In the encryption algorithm used by this encryption class, the cipher is initialized with a hardcoded key and IV. If users use class PasswordPlaceholderConfigurer to encrypt their password and configure it into kylin's configuration file, there is a risk that the password may be decrypted. This issue affects Apache Kylin 2 version 2.6.6 and prior versions; Apache Kylin 3 version 3.1.2 and prior versions; Apache Kylin 4 version 4.0.0 and prior versions.