Spring Security Default Spring Starter Security Basic Authentication Newline Bug

Describe the bug

Hello all, I don't know if this is really a bug, but it's possibly unwanted behavior when using basic auth (probably a very small use case). This is not so much a bug in the Spring Security framework, as it is in the procedures that caused it.

Environment: Spring Boot Starter Security 3.4.1 Kubernetes 1.27+ RedHat UBI9 Container Image

When using basic auth, with no customizations to the configuration, an password environment variable containing a newline character will cause the password to be "incorrect" when trying to curl with a non-newline password.

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Expected behavior A clear and concise description of what you expected to happen.

Sample

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Comment From: speedythesnail

Closed issue, was trying to create a draft so I can complete this later.