This advisory has been withdrawn because it is a duplicate of GHSA-4vpg-gwqq-w44c. This link is maintained to preserve external references.

SiYuan before v3.7.4 is missing authorization checks in 17 block metadata/content endpoints in kernel/api/block.go (including getRefText, checkBlockExist, and getBlockBreadcrumb). These handlers are gated only by basic authentication (model.CheckAuth) and lack publish-access filtering, allowing anonymous publish-mode readers to disclose private block content-derived text, structural metadata, and existence information for arbitrary block IDs across the workspace.