CVE-2026-100634

SiYuan before v3.8.4 does not validate the sender or restrict recipients in the 'siyuan-send-windows' IPC handler of the Electron main process (app/electron/main.js). The handler ignores event.sender and forwards any received payload to every BrowserWindow returned by BrowserWindow.getAllWindows(), including windows belonging to other opened workspaces. A renderer connected to an attacker-controlled remote kernel can therefore send {cmd: "lockscreenByMode"} and have it delivered across the workspace boundary; a sibling workspace window whose lockScreenMode is set to 1 invokes lockScreen(). Repeated messages allow the remote workspace to repeatedly lock unrelated local workspace windows, causing a limited denial of service. No confidentiality, integrity, or code-execution impact was observed.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/commit/8641553a1f07374001902d3ce773285db1292b2d
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm
https://www.vulncheck.com/advisories/siyuan-before-3.8.4-missing-authorization-via-siyuan-send-windows
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm

Configurations

No configuration.

History

30 Sep 2026, 13:17

Type	Values Removed	Values Added
References	~~() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm -~~	() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm -

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-10-08 16:16

NVD link : CVE-2026-100634

Mitre link : CVE-2026-100634

CVE.ORG link : CVE-2026-100634

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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