CRITICAL🇵🇱 Wersja polska

CVE-2026-34448

CVSS 9.0v3.1pub. 2026-03-31upd. 2026-07-24

SiYuan is a personal knowledge management system. Prior to version 3.6.2, an attacker who can place a malicious URL in an Attribute View mAsse field can trigger stored XSS when a victim opens the Gallery or Kanban view with “Cover From -> Asset Field” enabled. The vulnerable code accepts arbitrary http(s) URLs without extensions as images, stores the attacker-controlled string in coverURL, and injects it directly into an <img src="..."> attribute without escaping. In the Electron desktop client, the injected JavaScript executes with nodeIntegration enabled and contextIsolation disabled, so the XSS reaches arbitrary OS command execution under the victim’s account. This issue has been patched in version 3.6.2.

🤖 AI Analysis
How it works

The vulnerable code accepts any URLs with http(s) protocol as the image value in the 'Cover From -> Asset Field'. The attacker-controlled string is saved in the coverURL variable and inserted directly into the src attribute of the <img> tag without any escaping. When the victim opens the Gallery or Kanban view with the 'Cover From -> Asset Field' option enabled, the malicious JavaScript payload is executed. In the Electron client, the vulnerability has critical scope — the application runs with nodeIntegration enabled and contextIsolation disabled, which allows escape from the browser sandbox and execution of arbitrary operating system commands.

Impact

An attacker can execute arbitrary code at the operating system level in the context of the logged-in user account (RCE), which enables complete takeover of the victim's workstation, data theft, and further lateral movement in the network.

Mitigation & patch

SiYuan should be updated to version 3.6.2 or later, where the issue has been fixed. 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, particularly the Electron-based desktop client with nodeIntegration enabled and contextIsolation disabled

Analysis generated by Claude AI (Anthropic) based on NVD data. Always verify with vendor.
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/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
XSS
CWE
References

Related vulnerabilities

CVE-2026-40322CRITICAL9.0PL ✓same product

B3Log SiYuan: XSS w diagramach Mermaid eskaluje do RCE w Electron

CVE-2026-39846CRITICAL9.0PL ✓same product

RCE przez stored XSS w kliencie desktopowym B3Log SiYuan

CVE-2026-34449CRITICAL9.6PL ✓same product

RCE w SiYuan poprzez nadmiernie permisywną politykę CORS

CVE-2026-33670CRITICAL9.8PL ✓same product

Path Traversal w B3Log SiYuan — nieautoryzowane odczytywanie struktury plików

CVE-2026-33669CRITICAL9.8PL ✓same product

B3Log SiYuan — nieuprawniony odczyt treści dokumentów przez API