The Relevanssi WordPress plugin before 4.22.0, Relevanssi Premium WordPress plugin before 2.25.0 allows any unauthenticated user to read draft and private posts via a crafted request
https://www.relevanssi.com/release-notes/premium-2-25-free-4-22-release-notes/
https://wpscan.com/vulnerability/0c96a128-4473-41f5-82ce-94bba33ca4a3/