9.9
CRITICAL CVSS 3.1
CVE-2026-54067
SiYuan: Stored XSS to RCE via CSS-snippet <style> breakout in renderSnippet()
Description

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, CSS snippet body containing </style> breaks out of its surrounding <style> tag when renderSnippet() interpolates it via insertAdjacentHTML. A payload like runs arbitrary JavaScript in the renderer. On Electron desktop builds the renderer runs with nodeIntegration:true, so require('child_process') is reachable from the injected handler and the XSS chains to host RCE. Snippets sync via the workspace repository, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that pulls. The bug also bypasses the user's enabledCSS / enabledJS separation. A user who turned enabledJS off was making a deliberate call not to run untrusted JavaScript; the CSS path runs it anyway. This vulnerability is fixed in 3.7.0.

INFO

Published Date :

June 24, 2026, 10:16 p.m.

Last Modified :

June 25, 2026, 4:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-54067 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 B3log siyuan
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 CRITICAL MITRE-CVE
CVSS 3.1 CRITICAL [email protected]
Solution
Update SiYuan to version 3.7.0 or later to fix arbitrary JavaScript execution.
  • Update SiYuan to version 3.7.0 or later.
  • Review and sanitize CSS snippets from untrusted sources.
  • Disable snippet syncing if updates are not immediate.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-54067.

URL Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvjr-vv3c-w4qv
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvjr-vv3c-w4qv
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-54067 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-54067 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-54067 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 25, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvjr-vv3c-w4qv
    Added SSVC {'id': 'CVE-2026-54067', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-25T15:29:14.922467Z'}
  • New CVE Received by [email protected]

    Jun. 24, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'siyuan-note', 'product': 'siyuan', 'versions': [{'status': 'affected', 'version': '< 3.7.0'}]}]
    Added Description SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, CSS snippet body containing </style> breaks out of its surrounding <style> tag when renderSnippet() interpolates it via insertAdjacentHTML. A payload like runs arbitrary JavaScript in the renderer. On Electron desktop builds the renderer runs with nodeIntegration:true, so require('child_process') is reachable from the injected handler and the XSS chains to host RCE. Snippets sync via the workspace repository, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that pulls. The bug also bypasses the user's enabledCSS / enabledJS separation. A user who turned enabledJS off was making a deliberate call not to run untrusted JavaScript; the CSS path runs it anyway. This vulnerability is fixed in 3.7.0.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
    Added CWE CWE-79
    Added CWE CWE-1188
    Added Reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvjr-vv3c-w4qv
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.