Pipeline GitHub Notify Step Plugin 1.0.4 and earlier provides a list of applicable credential IDs to allow users configuring the plugin to select the one to use.
This functionality does not correctly check permissions, allowing any user with Overall/Read permission to get a list of valid credentials IDs. Those can be used as part of an attack to capture the credentials using another vulnerability.
An enumeration of credentials IDs in Pipeline GitHub Notify Step Plugin 1.0.5 requires the permission to configure a project.