---
id: CVE-2026-100640
title: >-
  SiYuan before v3.8.4 contains an authorization omission in the siyuan-get IPC
  handler that allows remote-kernel renderers to access native clipboard formats
  by invoking clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS
  comma…
summary: >-
  SiYuan before v3.8.4 contains an authorization omission in the siyuan-get IPC
  handler that allows remote-kernel renderers to access native clipboard formats
  by invoking clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS
  comma…
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N'
cwe:
  - CWE-200
vendor: siyuan-note
product: siyuan
affected:
  - siyuan < 3.8.4
published: '2026-09-26'
updated: '2026-09-26'
sourceUpdated: '2026-09-26T14:16:46.020'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100640'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mjmm-hgmc-m7qf
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-before-3.8.4-clipboard-data-disclosure-via-ipc
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-26T13:33:20.924Z'
---

## Overview

SiYuan before v3.8.4 contains an authorization omission in the siyuan-get IPC handler that allows remote-kernel renderers to access native clipboard formats by invoking clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS commands with matching plaintext. Attackers controlling remote renderer content can obtain MathML formulas, Office bytes, and WPS bytes from local clipboard during user-mediated paste operations.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.