SiYuan before v3.7.4 contains an information disclosure vulnerability in the /api/notebook/getNotebookInfo endpoint that returns notebook metadata without authorization checks. Attackers can read notebook names, document counts, sizes, and timestamps for closed or non-published notebooks that should be hidden from readers.

SiYuan before v3.7.4 contains an access control bypass vulnerability where static-file routes in the server mux bypass publish-access controls enforced on the REST API. Attackers with publish reader tokens or anonymous access in disabled-auth mode can read templates, snippets, and export artifacts by directly accessing static routes that lack the same restrictions as their REST API counterparts.

SiYuan before v3.7.4 fails to properly validate publish access for encrypted notebooks, treating them as publicly accessible by default. Anonymous readers can enumerate and retrieve fully decrypted document content from unlocked encrypted notebooks through the publish API without authentication or key material.

SiYuan versions before v3.7.4 contain an information disclosure vulnerability in the getEncryptedNotebookStatus endpoint that returns encrypted notebook identifiers, names, and lock states without publish-access filtering. Anonymous readers and publish-mode accounts can enumerate all encrypted notebooks and their current unlock status, revealing sensitive notebook names and decryption state in memory.

SiYuan versions <= v3.7.2 (patched in v3.7.4) contain an authentication bypass vulnerability in the kernel's CheckAuth function, which grants the administrator role (RoleAdministrator) to any request whose RemoteAddr is loopback (127.0.0.1) for a specific set of endpoints (including /api/system/exit, getNetwork, getWorkspaceInfo, /assets/*, and /export/*). These localhost bypasses sit outside the access auth code gate, so they apply even when an access auth code is configured. Because the fixed-port reverse proxy forwards requests to the kernel over loopback without injecting an authentication token and does not configure trusted proxies, a request forwarded through this proxy reaches the kernel with RemoteAddr = 127.0.0.1. If the fixed-port proxy is bound to a network interface, this could allow a remote unauthenticated attacker to obtain admin access on the affected endpoints; however, per the advisory this remote forwarding behavior was established only by code inspection and was not reproduced end-to-end.

SiYuan versions before v3.7.3 contain a metadata disclosure vulnerability in the /api/block/getBlockInfo endpoint that returns document root metadata including title for publish-forbidden documents without publish-access checks. Anonymous readers or publish RoleReader tokens can supply a block ID to retrieve the title, notebook, path, root ID, and icon of documents administrators marked as excluded from publishing.

SiYuan versions before v3.7.3 contain an authentication bypass vulnerability in publish mode where content-returning endpoints getHeadingChildrenDOM, getHeading*Transaction, and getBacklinkDoc perform no password check despite protecting the primary getDoc endpoint. Anonymous attackers can retrieve full content of password-protected documents by obtaining internal block IDs from reader-accessible endpoints and calling unprotected content endpoints to bypass the password gate.

SiYuan versions before v3.7.3 contain SQL injection vulnerabilities in the fullTextSearchAssetContent endpoint reachable by unauthenticated users and publish RoleReader tokens. Attackers can execute arbitrary SQL on the read-write asset-content database via unescaped method parameters and REGEXP clauses to read, modify, or delete cross-notebook data.

SiYuan versions before v3.7.3 contain an information disclosure vulnerability in the getHeadingDeleteTransaction, getHeadingLevelTransaction, and getHeadingInsertTransaction endpoints that return rendered block DOM without publish-access checks. Anonymous readers or publish RoleReader tokens can supply a heading block ID to read full rendered content of publish-disabled documents that should be restricted.

SiYuan before v3.7.3 contains a SQL injection vulnerability in the /api/filetree/searchDocs endpoint, where the caller-supplied keyword parameter is concatenated directly into SQL statements with no escaping or parameter binding. The endpoint is reachable by a publish RoleReader token, or unauthenticated when publish mode is enabled with Publish.Auth.Enable set to false. Because the statement executes on a read-write SQLite handle via a driver that supports stacked (semicolon-separated) statements, an attacker can read and modify database content across all cleartext (non-encrypted) notebooks on the instance.