Cross-Site Scripting (XSS) in SiYuan (CVE-2026-55570)
Summary
Cross-site scripting in SiYuan (CVE-2026-55570). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 3.7.0 or later.
Original description
The description as published by the source.
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, it does not escape the untrusted fields (name, version, author, description) when they are serialized into the data-obj HTML attribute of each marketplace card. Because the attribute is single-quoted and the value is produced with JSON.stringify() (which does not escape ', <, or >), a package whose name contains a single quote breaks out of the attribute and injects arbitrary HTML. In the desktop client the main BrowserWindow runs with nodeIntegration: true, contextIsolation: false, so the injected markup escalates from DOM XSS to arbitrary OS command execution. This is the same root cause and same impact as the original advisory, reached through a sibling sink the patch did not cover. This vulnerability is fixed in 3.7.0.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-55570 has been found in SiYuan.
Successful exploitation can lead to full system takeover. CVSS score: 9.0/10.
What to do: upgrade SiYuan to 3.7.0 or later.
If unsure, ask your IT team or search "SiYuan CVE-2026-55570" on the vendor's site.
CVE-2026-55570 (SiYuan) — CWE-79 / CVSS v3 9.0
Attack vector: remote (network-reachable)
Patched: 3.7.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Cross-site scripting (XSS) (CWE-79) exists in SiYuan.
Check the vendor advisory for the affected versions of SiYuan.
Severity: Critical (CVSS 9.0/10). Successful exploitation can lead to full system takeover.
Update to 3.7.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'SiYuan' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'SiYuan' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
SiYuanを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade SiYuan to 3.7.0ステージング環境で 3.7.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov