Improper Certificate Validation
It was discovered that rpm-ostree and rpm-ostree-client before 2017.3 fail to properly check GPG signatures on packages when doing layering. Packages with unsigned or badly signed content could fail to be rejected as expected. This issue is partially mitigated on RHEL Atomic Host, where certificate pinning is used by default.
CWE-295 - Improper Certificate Validation
The authenticity component of a web system stems from the ability to validate “Digital certificates”, which (i) establish trust between two or more entities sharing data over a network; (ii) ensure data at rest and transit is secure from unauthorized access; and (iii) check the identity of the actors that interact with the system. An application with absent or ineffective certificate validation mechanisms allows malicious users, impersonating trusted hosts, to manipulate the communication path between the client and the host, resulting in unauthorized access to data and to the application’s internal environment, and potentially enabling man-in-the-middle attacks.