---
title: "CVE-2026-34449: SiYuan is Vulnerable to Cross-Origin RCE via Permissive CORS Policy and JavaScript Snippet Injection"
url: https://erroneo.us/security/cve/CVE-2026-34449/
description: "CVE-2026-34449 (github.com/siyuan-note/siyuan/kernel (Go)): SiYuan is a personal knowledge management system. Prior to version 3.6.2, a malicious website…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-03-31
date_modified: 2026-04-06
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-34449"
kev: false
cvss: 9.7
epss: 0.00803
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-34449: SiYuan is Vulnerable to Cross-Origin RCE via Permissive CORS Policy and JavaScript Snippet Injection

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.8% , percentile 56: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 56% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
- Only applies if your dependency tree includes github.com/siyuan-note/siyuan/kernel (Go) <= 3.6.1, fixed in 3.6.2 . Check your lockfile, including transitive dependencies.

## What it is

SiYuan is a personal knowledge management system. Prior to version 3.6.2, a malicious website can achieve Remote Code Execution (RCE) on any desktop running SiYuan by exploiting the permissive CORS policy (Access-Control-Allow-Origin: + Access-Control-Allow-Private-Network: true) to inject a JavaScript snippet via the API. The injected snippet executes in Electron's Node.js context with full OS access the next time the user opens SiYuan's UI. No user interaction is required beyond visiting the malicious website while SiYuan is running. This issue has been patched in version 3.6.2.

## Affected packages

- Go `github.com/siyuan-note/siyuan/kernel` <= 3.6.1 → fixed: 3.6.2

## Affected products (CVE record)

- siyuan-note siyuan: < 3.6.2

## Severity

- GitHub_M CVSS 3.1: 9.7 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.6 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.80% probability of exploitation activity in the next 30 days; percentile 56.

## Sources

- [GitHub Advisory GHSA-68p4-j234-43mv](https://github.com/advisories/GHSA-68p4-j234-43mv)
- [CVE.org record CVE-2026-34449](https://www.cve.org/CVERecord?id=CVE-2026-34449)
- [NVD entry CVE-2026-34449](https://nvd.nist.gov/vuln/detail/CVE-2026-34449)
- [github.com](https://github.com/siyuan-note/siyuan/security/advisories/GHSA-68p4-j234-43mv)
- [github.com](https://github.com/siyuan-note/siyuan/issues/17246)
- [github.com](https://github.com/siyuan-note/siyuan/releases/tag/v3.6.2)

---
Source page: https://erroneo.us/security/cve/CVE-2026-34449/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt