---
id: CVE-2026-75916
title: >-
  SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the '(('
  block-reference autocomplete hint popup
summary: >-
  SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the '(('
  block-reference autocomplete hint popup. In genHintItemHTML()
  (app/src/protyle/hint/extend.ts), a candidate block's name, alias, and memo
  fields are concatena…
severity: high
cvss: 8.6
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H'
cwe:
  - CWE-79
vendor: siyuan-note
product: siyuan
affected:
  - siyuan (all versions)
published: '2026-08-19'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T16:17:41.530'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-75916'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5prr-vgxq-69g9
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-xss-to-rce-via-unescaped-block-metadata-in-hint-popup
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5prr-vgxq-69g9
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-08-21T19:21:47.693296Z'
epss: 0.00243
epssPercentile: 0.14244
ingestedAt: '2026-10-08T16:52:14.722Z'
---

## Overview

SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the '((' block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block's name, alias, and memo fields are concatenated into the popup's HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. <img src=x onerror=...>) that executes automatically when a victim types '((' followed by a search term that surfaces the crafted block. Because SiYuan's Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require('child_process') access, allowing the XSS to escalate to arbitrary OS command execution.

## Remediation

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