Grav CMS 2.0.7 through 2.0.10 Arbitrary Method Invocation via Blueprint

Grav CMS versions 2.0.7 through 2.0.10 fail to validate fully-qualified static method calls (Class::method) in blueprint dynamic-field directives because Blueprint::isSafeDynamicCall() only applies its dangerous-callable denylist to strings that do not contain '::'. An account with only page-editing rights (admin.pages, not super-admin or admin.pages_twig) can plant a directive in a page's form-field frontmatter that invokes an arbitrary public static PHP method with attacker-controlled arguments. Using built-in gadget methods this allows reading of any server-readable file (disclosed to anonymous visitors of the crafted page) and arbitrary creation/copying of files and directories under the web-server account. Fixed in 2.0.11.