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TI-2026-39000 Aliases CVE-2026-54069GHSA-hvr9-72v2-fff3

SiYuan: Unauthenticated Admin API Access via Blanket chrome-extension:// Origin Allowlist

Priority HIGH 75CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-346.

Summary

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, SiYuan Note's kernel HTTP server unconditionally trusts all chrome-extension:// origins, granting RoleAdministrator access to every installed browser extension without any authentication. Combined with the default empty AccessAuthCode on desktop installs, any Chrome/Chromium extension -- including a compromised legitimate extension via supply chain attack -- can make fully authenticated admin API calls to the SiYuan kernel at 127.0.0.1:6806, enabling data exfiltration, stored XSS injection, and configuration tampering. This vulnerability is fixed in 3.7.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.07475 94th percentileScored 2026-11-07
Fix Fixed siyuan (siyuan-note): 3.7.0github.com/siyuan-note/siyuan/kernel (Go): 0.0.0-20260628153353-2d5d72223df4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
siyuan-notesiyuanbefore 3.7.03.7.0Patch availableCNA
—github.com/siyuan-note/siyuan/kernel (Go)before 0.0.0-20260628153353-2d5d72223df40.0.0-20260628153353-2d5d72223df4Patch availableGHSA-hvr9-72v2-fff3
  • siyuan Vendorsiyuan-note Affected before 3.7.0 Fixed in 3.7.0 Patch available CNA
  • github.com/siyuan-note/siyuan/kernel (Go) Vendor— Affected before 0.0.0-20260628153353-2d5d72223df4 Fixed in 0.0.0-20260628153353-2d5d72223df4 Patch available GHSA-hvr9-72v2-fff3

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*——siyuan-note
  • cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:* Versions — — ·siyuan-note

Remediation

  • Fix · CNA siyuan (siyuan-note) Fixed in 3.7.0
  • Fix · GHSA-hvr9-72v2-fff3 github.com/siyuan-note/siyuan/kernel (Go) Fixed in 0.0.0-20260628153353-2d5d72223df4 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54069
  2. 2026-10-03 Alias added: GHSA-hvr9-72v2-fff3
  3. 2026-10-26 EPSS moved to the 90th–95th percentile

References

Advisory 1

Other 2

  • TI-2026-48492 SiYuan before v3.7.3 SQL Injection via searchDocs CVSS 4.0CRITICAL 9.9
  • TI-2026-48491 SiYuan before v3.7.3 SQL Injection via searchEmbedBlock CVSS 4.0CRITICAL 9.9
  • TI-2026-48490 SiYuan before v3.7.3 SQL Injection via fullTextSearchAssetContent CVSS 4.0CRITICAL 9.9
  • TI-2026-47010 SiYuan before v3.7.2 Unauthenticated Administrator Takeover via MCP CVSS 4.0CRITICAL 10.0
  • TI-2026-26050 SiYuan has directory traversal within its publishing service CVSS 3.1CRITICAL 9.8
  • TI-2026-25256 SiYuan: Authorization Bypass Allows Arbitrary SQL Execution via Search API CVSS 3.1CRITICAL 9.8
See all 242 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences