SiYuan versions before v3.7.4 contain an information disclosure vulnerability in the getBookmarkLabels endpoint that returns all bookmark labels in the workspace without publish-access filtering. Anonymous readers and publish-mode readers can obtain the complete bookmark vocabulary across the workspace, disclosing subject matter and organizational information from inaccessible documents.

SiYuan versions before v3.7.4 contain an information disclosure vulnerability in the getAttributeViewBacklinks endpoint that consults the forbidden access list instead of the visibility list when filtering backlinks. Anonymous readers can supply a publicly visible database row identifier to discover hidden-tier documents that reference it, receiving the database name, row title, and document path of hidden documents.

SiYuan versions before v3.7.4 contain an information disclosure vulnerability in the getRefIDsByFileAnnotationID endpoint that returns block identifiers citing PDF annotations without publish-access filtering. Attackers can extract block identifiers from restricted documents by supplying annotation identifiers visible in published pages, revealing citation relationships across forbidden and password-protected tiers.

SiYuan before v3.7.4 contains an information disclosure vulnerability in the /api/filetree/authFilePublishAccess endpoint, which is registered with CheckAuth only and is reachable anonymously. The endpoint never sets a failure code, so its outcome is signalled entirely by the response message and by the presence of a Set-Cookie header, and these signals differ across access tiers. By submitting requests with an empty password for a candidate document identifier, an anonymous attacker can distinguish whether a document is public/nonexistent, password-protected, or exists at the hidden or forbidden tier, thereby confirming the existence of documents they are not permitted to access. Because hidden and forbidden entries store an empty password, such requests also cause the server to issue a publish-auth cookie for forbidden documents.

SiYuan versions before v3.7.4 contain a publish-boundary bypass vulnerability in WebSocket broadcast sessions that allows anonymous readers to receive unfiltered edits. Attackers can establish a WebSocket connection to the publish surface and passively receive real-time content events including password-protected and forbidden documents without authentication.

SiYuan versions before v3.7.4 contain a missing authorization vulnerability in the /api/ref/refreshBacklink endpoint that allows anonymous readers to trigger persistent server-side writes. Attackers can invoke the endpoint with an attacker-controlled block ID to flush transaction queues, scan all references globally, and enqueue database writes, bypassing read-only protections and enabling resource amplification attacks.

SiYuan versions <= v3.7.2 contain a SQL injection vulnerability in the backlink/mention search query (kernel/model/backlink.go), which concatenates stored block metadata (title, name, alias, anchor text) and the client-supplied keyword into a SQL MATCH/search statement while escaping only the double-quote character and not the single quote. A single quote in the client keyword (first-order, reachable by an anonymous or RoleReader user on the publish surface) or in stored document metadata (second-order) breaks out of the string literal. Because the query runs on the main read-write siyuan.db handle via a statement-stacking-capable driver, an attacker can execute arbitrary SQL, enabling cross-notebook read and write. Fixed in v3.7.4.

SiYuan's development branch (endpoint introduced by commit 9b8e8956f, not present in v3.7.3 or master, patched in v3.7.4) contains a missing-authorization vulnerability in the /api/av/getAttributeViewSearchTarget endpoint. The route is registered with CheckAuth only and performs no authorization checks (no CheckReadonly, no publish-access or encrypted-notebook gating). Given a database identifier taken from a published page and a keyword, an anonymous reader can query the endpoint to retrieve matching database row content, including rows that publish filters (FilterAttributeViewByPublishAccess) would otherwise withhold. No released stable version is affected.

SiYuan versions before v3.7.4 contain an information disclosure vulnerability in the /api/storage/getOutlineStorage endpoint that performs no authorization checks. Attackers can retrieve outline state including heading identifiers for any document by supplying its identifier, even for documents forbidden to the requester.

SiYuan before v3.7.4 contains an information disclosure vulnerability in the local storage filter that returns the administrator's entire storage map with only three keys sanitized. Unauthenticated attackers or publish readers can retrieve closed-tab history, search keywords, private document identifiers, and expanded folder paths by calling the getLocalStorage endpoint.

SiYuan versions before v3.7.4 contain an information disclosure vulnerability in the /api/block/getRefIDs endpoint that fails to check password-protected document tiers. Unauthenticated readers can discover that password-protected documents reference specific blocks and obtain block identifiers without entering the document password.

SiYuan versions before v3.7.4 contain a path traversal vulnerability in the getUniqueFilename endpoint that allows anonymous readers to probe filesystem existence without validation or confinement. Attackers can supply arbitrary absolute paths to determine whether files and directories exist on the host, enabling reconnaissance of the filesystem layout and installed software.