Exposure of Sensitive Information to an Unauthorized Actor
The version checking subroutine in percona-toolkit before 2.2.13 and xtrabackup before 2.2.9 was vulnerable to silent HTTP downgrade attacks and Man In The Middle attacks in which the server response could be modified to allow the attacker to respond with modified command payload and have the client return additional running configuration information leading to an information disclosure of running configuration of MySQL.
CWE-200 - Information Exposure
An information exposure vulnerability is categorized as an information flow (IF) weakness, which can potentially allow unauthorized access to otherwise classified information in the application, such as confidential personal information (demographics, financials, health records, etc.), business secrets, and the application's internal environment.