The Meow Gallery WordPress plugin before 5.5.2 does not escape an attachment's alt text before outputting it into an attribute of the link it builds for linked galleries, allowing users with the Auth…

Summary

The Meow Gallery WordPress plugin before 5.5.2 does not escape an attachment's alt text before outputting it into an attribute of the link it builds for linked galleries, allowing users with the Author role or above to store a JavaScript payload that executes in the browser of any visitor (including administrators) who views a post containing such a gallery.