Relying on the latest tag for container images can introduce several risks to the security and reliability of a Kubernetes environment:
Lack of Uniqueness: The latest tag does not uniquely define a container image version. Multiple builds of the same image can share the latest tag, making it impossible to determine which version is deployed. This can lead to unpredictable behavior and inconsistencies in the environment.
Non-Persistent Tagging: The latest tag is not fixed and can change over time as new versions of the image are pushed. This can cause an application to pull an unintended version of the image, leading to issues such as incompatibility, untested changes, or the introduction of vulnerabilities.
Loss of Control: When the latest tag is used, control over which version is deployed is effectively lost. This can result in arbitrary and unverified image versions being deployed, which might not have been thoroughly tested or secured.
To mitigate these risks, proper versioning practices must be implemented.