GHSA-vpjw-wf5h-cgpq SiYuan: Graph endpoints omit the publish-password tier: anonymous readers receive block-level content of password-protected documents

• Go github.com/siyuan-note/siyuan/kernel: < 0.0.0-20260724091654-82e9ded423e4 → fixed in 0.0.0-20260724091654-82e9ded423e4

CVE: This vulnerability corresponds to CVE-2026-72804. Summary `getGraph` and `getLocalGraph` filter reader sessions against the *visibility* tier only and never check the publish password. Password-protected documents are `Visible = true`, so their graph nodes survive the filter and graph nodes are block-level and carry the block's actual content. An anonymous reader who has never supplied a document's password can therefore retrieve that document's per-block content and its reference/backlink topology. Both endpoints are `CheckAuth`-only, so they are reachable by the publish `RoleReader` token and by the anonymous account when `Publish.Auth.Enable` is `false`. Details Both handlers filter with the invisible-tier set only: ```go publishIgnore := model.GetInvisiblePublishAccess(publishAccess) // Visible tier ONLY nodes, links = model.FilterGraphByPublishIgnore(publishIgnore, nodes, links) ``` `FilterGraphByPublishIgnore` (`kernel/model/publish_access.go:849`) drops a node only when `!CheckPathAccessableByPublishIgnore(node.Box, node.Path, publishIgnore)`. There is no password evaluation anywhere in the graph code grepping `graph.go` for `CheckPublishAuthCookie` or `password` returns nothing. Because password-protected documents are `Visible = true`, their nodes pass the filter unchanged. The nodes carry content, not just titles. `genTreeNodes` emits one node per block, and `nodeTitleLabel` sets `node.Title = node.Label = block.Content` (`kernel/model/graph.go:673-678`). So each surviving node exposes the block's text. This is materially broader than the by-design listing behaviour: `listDocsByPath` intentionally exposes protected document *titles* (protected means "publicly visible, password required to access"), but the graph endpoints expose per-block *content* and the full link/reference topology, which listing never does. Verified at `origin/master`: `FilterGraphByPublishIgnore` contains only the `CheckPathAccessableByPublishIgnore` call; `graph.go` contains no password check; both routes are registered `CheckAuth` without `CheckAdminRole`. Proof of Concept Precondition: publish mode enabled (default port 6808); anonymous when `Publish.Auth.Enable` is `false`, otherwise any publish reader account. A document is marked protected (visible, password set) and contains blocks with distinctive content. No password is supplied in any request below. Targeted: one protected document's content and reference structure: ``` POST http://127.0.0.1:6808/api/graph/getLocalGraph {"id":""} ``` Returns nodes whose `Title`/`Label` contain the protected document's per-block content, plus its links/backlinks. Workspace-wide: every protected document: ``` POST http://127.0.0.1:6808/api/graph/getGraph {} ``` Returns block-level nodes for every protected document in the workspace, together with the complete link graph. Control: requesting the same document through the normal content path returns the password placeholder confirming the password gate is enforced elsewhere and omitted here. Impact An anonymous reader (publish mode with auth disabled) or any publish `RoleReader` can read the block-level content of every password-protected document in the workspace, plus the full reference/backlink topology, without ever supplying a password. This defeats the publish-password control for the graph subsystem. Confidentiality-only, no modification. Suggested fix Extend the graph filter to evaluate the password tier in addition to visibility: in `FilterGraphByPublishIgnore`, drop a node unless the document's publish password is unset or the caller presents a valid publish-auth cookie for it (`password == "" || CheckPublishAuthCookie(...)`), matching the sibling filters that enforce both tiers. Consider also excluding block content from node `Title`/`Label` for reader sessions, so the graph conveys structure without document text.