CRITICAL🇵🇱 Wersja polska

CVE-2026-34449

CVSS 9.6v3.1pub. 2026-03-31upd. 2026-07-24

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.

🤖 AI Analysis
How it works

SiYuan exposes a local API with CORS headers set to 'Access-Control-Allow-Origin: *' and 'Access-Control-Allow-Private-Network: true', allowing any website to send requests to this API. A malicious website can inject a JavaScript code fragment through the API, which is saved and executed in the context of the Node.js engine of the Electron application when the SiYuan user interface is opened next. This process does not require any additional interaction from the victim beyond visiting the malicious website while the SiYuan application is running in the background.

Impact

Attacker gains full access to the victim's operating system with SiYuan process privileges, enabling execution of arbitrary commands, data theft, installation of malicious software, or further lateral movement in the network.

Mitigation & patch

SiYuan must be updated to version 3.6.2 or later, where the vulnerability has been patched. The patch is available in the official project repository: https://github.com/siyuan-note/siyuan/releases/tag/v3.6.2

Who is affected

B3Log SiYuan in all versions before 3.6.2 in the desktop variant (based on Electron)

Analysis generated by Claude AI (Anthropic) based on NVD data. Always verify with vendor.
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
  • B3log Siyuan

    APP
    B3Log
    < 3.6.2
🔵
CHECK WITH VENDOR
No clear patch data available. Check vendor references.
Tags
RCE
CWE
References

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