CVE-2026-39846

SiYuan is a personal knowledge management system. Prior to 3.6.4, a malicious note synced to another user can trigger remote code execution in the SiYuan Electron desktop client. The root cause is that table caption content is stored without safe escaping and later unescaped into rendered HTML, creating a stored XSS sink. Because the desktop renderer runs with nodeIntegration enabled and contextIsolation disabled, attacker-controlled JavaScript executes with access to Node.js APIs. In practice, an attacker can import a crafted note into a synced workspace, wait for the victim to sync, and achieve code execution when the victim opens the note. This vulnerability is fixed in 3.6.4.

CVSS v3 9.0 CRITICAL

9.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phhp-9rm9-6gr2	Exploit Vendor Advisory
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phhp-9rm9-6gr2	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*

History

16 Apr 2026, 04:32

Type	Values Removed	Values Added
First Time		B3log B3log siyuan
References	~~() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phhp-9rm9-6gr2 -~~	() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phhp-9rm9-6gr2 - Exploit, Vendor Advisory
CPE		cpe:2.3:a:b3log:siyuan::::::::

08 Apr 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phhp-9rm9-6gr2 -~~	() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-phhp-9rm9-6gr2 -

07 Apr 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-07 22:16

Updated : 2026-04-16 04:32

NVD link : CVE-2026-39846

Mitre link : CVE-2026-39846

CVE.ORG link : CVE-2026-39846

JSON object : View

Products Affected

b3log

siyuan

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-94

Improper Control of Generation of Code ('Code Injection')

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