📄 Description (English)
SiYuan is a personal knowledge management system. Prior to version 3.6.2, a vulnerability allows crafted block attribute values to bypass server-side attribute escaping when an HTML entity is mixed with raw special characters. An attacker can embed a malicious IAL value inside a .sy document, package it as a .sy.zip, and have the victim import it through the normal Import -> SiYuan .sy.zip workflow. Once the note is opened, the malicious attribute breaks out of its original HTML context and injects an event handler, resulting in stored XSS. In the Electron desktop client, this XSS reaches remote code execution because injected JavaScript runs with access to Node/Electron APIs. This issue has been patched in version 3.6.2.
🤖 AI Executive Summary
CVE-2026-34585 is a critical stored XSS vulnerability in SiYuan knowledge management system (versions before 3.6.2) that allows attackers to inject malicious code through crafted block attributes in .sy.zip files. When imported and opened, the XSS payload executes with Node/Electron API access in desktop clients, enabling remote code execution. The vulnerability is actively exploitable and poses significant risk to organizations using SiYuan for sensitive document management.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: Apr 24, 2026 02:47
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability poses significant risk to Saudi government agencies, research institutions, and enterprises using SiYuan for classified or sensitive document management. High-risk sectors include: (1) Government/NCA — potential compromise of internal knowledge bases and policy documents; (2) Banking/SAMA — risk to financial analysis and compliance documentation systems; (3) Healthcare — exposure of medical research and patient information repositories; (4) Energy/ARAMCO — threat to technical documentation and operational knowledge systems; (5) Education — compromise of research and academic materials. The RCE capability in Electron clients enables lateral movement and data exfiltration across organizational networks.
🏢 Affected Saudi Sectors
Government
Banking
Healthcare
Energy
Education
Research Institutions
Telecommunications
🎯 MITRE ATT&CK Techniques
T1190 — Exploit Public-Facing Application (SiYuan import functionality)
T1566.001 — Phishing: Spearphishing Attachment (.sy.zip files)
T1059.001 — Command and Scripting Interpreter: PowerShell (RCE via Electron APIs)
T1059.004 — Command and Scripting Interpreter: Unix Shell (RCE on Linux/macOS)
T1203 — Exploitation for Client Execution (XSS to RCE chain)
T1059.007 — Command and Scripting Interpreter: JavaScript (XSS payload execution)
T1547.013 — Boot or Logon Initialization Scripts: XSS persistence mechanism
T1005 — Data from Local System (exfiltration via RCE)
T1041 — Exfiltration Over C2 Channel (data theft post-compromise)
⚖️ Saudi Risk Score (AI)
8.8
/ 10.0
🔧 Remediation Steps (English)
IMMEDIATE ACTIONS:
1. Identify all SiYuan installations across your organization using asset discovery tools
2. Restrict import functionality for .sy.zip files until patching is complete
3. Disable SiYuan Electron desktop client if not critical to operations
4. Audit recent .sy.zip imports and review imported documents for suspicious attributes
PATCHING GUIDANCE:
1. Upgrade SiYuan to version 3.6.2 or later immediately
2. For web-based deployments, update the server component and restart services
3. For Electron clients, force update through your deployment mechanism
4. Verify patch installation by checking version in Settings > About
COMPENSATING CONTROLS (if immediate patching not possible):
1. Implement network segmentation to isolate SiYuan systems
2. Disable JavaScript execution in SiYuan settings if available
3. Restrict user permissions to prevent .sy.zip imports
4. Monitor file system for suspicious process spawning from SiYuan processes
5. Implement application whitelisting on systems running SiYuan
DETECTION RULES:
1. Monitor for .sy.zip file imports with suspicious IAL (Inline Attribute List) values containing HTML entities mixed with special characters (e.g., <, >, onclick, onerror)
2. Alert on SiYuan process spawning child processes (cmd.exe, powershell.exe, bash, etc.)
3. Monitor for unusual network connections initiated from SiYuan processes
4. Log and review all document imports from external sources
5. Implement EDR rules to detect XSS payload patterns in file attributes
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. تحديد جميع تثبيتات SiYuan عبر مؤسستك باستخدام أدوات اكتشاف الأصول
2. تقييد وظيفة الاستيراد لملفات .sy.zip حتى يتم إكمال التصحيح
3. تعطيل عميل SiYuan Electron إذا لم يكن حرجاً للعمليات
4. تدقيق استيرادات .sy.zip الأخيرة ومراجعة المستندات المستوردة للبحث عن سمات مريبة
إرشادات التصحيح:
1. ترقية SiYuan إلى الإصدار 3.6.2 أو أحدث فوراً
2. للنشر القائم على الويب، قم بتحديث مكون الخادم وإعادة تشغيل الخدمات
3. لعملاء Electron، فرض التحديث من خلال آلية النشر الخاصة بك
4. التحقق من تثبيت التصحيح بالتحقق من الإصدار في الإعدادات > حول
الضوابط البديلة (إذا لم يكن التصحيح الفوري ممكناً):
1. تنفيذ تقسيم الشبكة لعزل أنظمة SiYuan
2. تعطيل تنفيذ JavaScript في إعدادات SiYuan إن أمكن
3. تقييد أذونات المستخدم لمنع استيراد .sy.zip
4. مراقبة نظام الملفات للبحث عن عمليات مريبة تنبثق من عمليات SiYuan
5. تنفيذ قائمة بيضاء للتطبيقات على الأنظمة التي تقوم بتشغيل SiYuan
قواعد الكشف:
1. مراقبة استيرادات ملفات .sy.zip بقيم IAL مريبة تحتوي على كيانات HTML مختلطة مع أحرف خاصة
2. التنبيه عند عملية SiYuan التي تنبثق عمليات فرعية
3. مراقبة الاتصالات الشبكية غير العادية التي تبدأ من عمليات SiYuan
4. تسجيل ومراجعة جميع استيرادات المستندات من مصادر خارجية
5. تنفيذ قواعد EDR للكشف عن أنماط حمولة XSS في سمات الملفات
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.5.1.1 — Information Security Policies (secure software update procedures)
ECC 2024 A.5.2.1 — User Access Management (restrict import functionality)
ECC 2024 A.6.1.1 — Cryptography (validate file integrity during import)
ECC 2024 A.7.1.1 — Physical and Environmental Security (network segmentation)
ECC 2024 A.8.1.1 — Operations Security (vulnerability management and patching)
🔵 SAMA CSF
SAMA CSF Governance Domain — Vulnerability Management (identify and patch CVE-2026-34585)
SAMA CSF Protective Domain — Access Control (restrict .sy.zip imports)
SAMA CSF Protective Domain — Data Protection (prevent XSS-based data exfiltration)
SAMA CSF Detective Domain — Monitoring and Logging (detect malicious imports and RCE attempts)
SAMA CSF Responsive Domain — Incident Response (prepare response procedures for compromised systems)
🟡 ISO 27001:2022
ISO 27001:2022 A.5.1 — Policies for information security (software vulnerability management)
ISO 27001:2022 A.5.2 — Information security roles and responsibilities (patch management ownership)
ISO 27001:2022 A.6.1 — Screening (vendor security assessment for SiYuan)
ISO 27001:2022 A.8.1 — User endpoint devices (secure configuration of SiYuan clients)
ISO 27001:2022 A.8.2 — Privileged access rights (restrict administrative access to SiYuan)
ISO 27001:2022 A.8.3 — Information access restriction (limit .sy.zip import permissions)
🔗 References & Sources 4
🔗
https://github.com/siyuan-note/siyuan/issues/17246
security-advisories@github.com
Issue Tracking
🔗
https://github.com/siyuan-note/siyuan/releases/tag/v3.6.2
security-advisories@github.com
Release Notes
🔗
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-ff66-236v-p4fg
security-advisories@github.com
Exploit
Vendor Advisory
🔗
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-ff66-236v-p4fg
134c704f-9b21-4f2e-91b3-4a467353bcc0
Exploit
Vendor Advisory
📦 Affected Products / CPE 1 entries
b3log:siyuan