CVE-2026-82651

SiYuan before v3.8.1 fails to properly escape block name, alias, and memo fields in hint, backlink, and breadcrumb rendering functions. Attackers can set a block's name to contain HTML/script tags that execute when another user views documents referencing or displaying that block.

SiYuan before v3.8.1 contains a stored cross-site scripting vulnerability in confirmDialog() where unescaped package names and notebook names are interpolated directly into innerHTML assignments. Attackers can submit malicious bazaar packages with HTML/script payloads in the name field that execute in users' browsers when uninstalling packages or unlocking encrypted notebooks.

SiYuan before v3.8.1 fails to filter invisible-tier content from SQL embed blocks, attribute-view keys, and attribute-view backlinks in publish mode. Anonymous readers can enumerate invisible content through these three listing mechanisms despite admin configuration marking content unlisted.

SiYuan 3.8.0 contains a path traversal / sensitive file exposure vulnerability in the RenderTemplate function (kernel/model/template.go), reachable via the POST /api/template/render endpoint (kernel/api/template.go). The endpoint restricts the supplied path only to the workspace directory (util.IsAbsPathInWorkspace) but, unlike the file API's refuseToAccess() blocklist, applies no sensitive-path exclusion. This allows an authenticated attacker to read sensitive workspace files, including conf/conf.json, which contains the API token and cookie signing key. The issue is fixed in v3.8.1.

SiYuan Windows installer before version 3.8.1 (affected versions >= 2.0.14) contains an uncontrolled search path element vulnerability in its NSIS installer, which invokes system executables such as TASKKILL by name rather than by absolute path. Because NSIS nsExec::Exec resolves these calls using a search path that includes the installer's own launch directory ahead of System32, an attacker who plants a malicious executable (e.g., a renamed TASKKILL.exe) in that directory can have it executed when the installer runs. These calls occur in electron-builder's preInit hook before the license page is displayed, and with an all-users (elevated) install the planted binary executes with an elevated token, resulting in local privilege escalation.

SiYuan is a knowledge management system that prior to version 3.7.0 had security vulnerabilities related to 8 ungated APIs that could modify configuration and SQL index. Users with a valid JWT token could access these APIs, leading to unauthorized changes to server state.

SiYuan is an open-source personal knowledge management system. Prior to 3.6.5, the fix for CVE-2026-30869 only added a denylist check but did not address the root cause – a redundant url.PathUnescape() call in serveExport(). An authenticated attacker can use double URL encoding to traverse directories and read arbitrary workspace files including the full SQLite database, kernel log, and all user documents.

SiYuan before v3.7.4 fails to validate the packageName parameter in Bazaar install and uninstall endpoints, allowing authenticated administrators to perform path traversal. Attackers with admin access can write arbitrary files or recursively delete directories by supplying crafted packageName values.

SiYuan before v3.7.4 fails to set Content-Disposition and X-Content-Type-Options headers when serving arbitrary file assets, allowing stored cross-site scripting attacks. Authenticated attackers can upload HTML files as assets and execute scripts with full kernel API access when the workspace owner opens the asset link.

SiYuan before 3.7.4 registers Go net/http/pprof debug endpoints including heap and goroutine dumps without authentication when --mode flag is not set to exactly prod. Attackers can access /debug/pprof/heap and related endpoints to extract in-memory secrets including AccessAuthCode and AI provider API keys.