CVE-2026-100634

SiYuan before v3.8.4 Missing Authorization via siyuan-send-windows

Published: Sep 26, 2026Updated: Sep 26, 2026 Sources: CVE List NVDCWE-862

4.7MEDIUM

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:CScope

Changed

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:LAvailability

Low

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Weaknesses

CWE-862

Affected Products

siyuan-note

commercial

siyuanOn-premDesktop App

Consumer Software / productivity

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

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References

https://github.com/siyuan-note/siyuan/commit/8641553a1f07374001902d3ce773285db1292b2d

github.com

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm

github.com

https://www.vulncheck.com/advisories/siyuan-before-3.8.4-missing-authorization-via-siyuan-send-windows

vulncheck.com

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