Slim SEO < 4.9.11 - Contributor+ Arbitrary Post Meta Disclosure

The Slim SEO WordPress plugin before 4.9.11 does not restrict a post-meta preview feature to posts the user is allowed to edit, verifying only read access, allowing users with the Contributor role to read arbitrary post meta, including protected and private keys, of published posts they do not own, including password-protected posts and posts of non-public post types.