Grav 2.0.15 before 2.2.13 contains an allowlist bypass vulnerability that allows page editors to invoke arbitrary public static methods by relocating data-*@ directives with unset-name@ or integer keys. Attackers with page-edit permission can embed crafted fields in Flex form overrides in page frontmatter to call methods like Folder::delete or Utils::download, deleting directories, overwriting files, or reading files outside the page tree.