CVE-2026-34449
9.6 · CRITICALOverview
CVE-2026-34449 is a critical-severity vulnerability affecting b3log siyuan. It was published on March 31, 2026 and has a CVSS 3.1 base score of 9.6 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 9.6, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
SiYuan is a personal knowledge management system. Prior to version 3.6.2, a malicious website can achieve Remote Code Execution (RCE) on any desktop running SiYuan by exploiting the permissive CORS policy (Access-Control-Allow-Origin: * + Access-Control-Allow-Private-Network: true) to inject a JavaScript snippet via the API. The injected snippet executes in Electron's Node.js context with full OS access the next time the user opens SiYuan's UI. No user interaction is required beyond visiting the malicious website while SiYuan is running. This issue has been patched in version 3.6.2.
Remediation
Check the references section for vendor advisories and patches from b3log. Update siyuan to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| b3log | siyuan | >= 0, < 3.6.2 | Affected |
Frequently Asked Questions
What is CVE-2026-34449?
CVE-2026-34449 is a critical-severity vulnerability affecting b3log siyuan. It was published on March 31, 2026 and has a CVSS 3.1 base score of 9.6 (CRITICAL).
How severe is CVE-2026-34449?
This vulnerability has a CVSS 3.1 base score of 9.6, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-34449?
Check the references section for vendor advisories and patches from b3log. Update siyuan to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-34449?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-34449 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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