TI-2026-80186 Aliases CVE-2026-116168 GHSA-659w-8mpv-qcqc

Path traversal in SiYuan MCP asset tool lets attackers read local files

MEDIUM 64CWE-22Published 2026-10-25 · Updated 2026-11-04

Key facts

Attack vector: Local
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-22 and the CVSS impact.

Summary

SiYuan before 3.8.7 contains a path traversal flaw (CWE-22) in its MCP asset tool, where the sensitive-path blacklist used by validateAssetUploadPaths is incomplete and omits files such as .env. An authenticated attacker who can use the MCP asset upload action can copy local secret files into the workspace and read them back over HTTP through /assets/.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

SiYuan before 3.8.7 contains a path traversal vulnerability in the MCP asset tool because validateAssetUploadPaths relies on an incomplete sensitive-path blacklist that omits .env and other secret files. Authenticated attackers driving the MCP asset upload action can copy such local files into the workspace and read them back via /assets/ over HTTP.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00186 8th percentileScored 2026-11-07

Fix Fixed siyuan (siyuan-note): 3.8.7

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

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

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
siyuan-note	siyuan	before 3.8.7	3.8.7	Patch available	CNA

siyuan Vendorsiyuan-note Affected before 3.8.7 Fixed in 3.8.7 Patch available CNA

CPE names Threatist (inferred) · 1

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

CPE	Versions	Role	Vendor
cpe:2.3:a:b3log:siyuan::::::::	—	—	siyuan-note

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

Remediation

Upgrade SiYuan to version 3.8.7 or later, which fixes the flaw.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Fix · CNA siyuan (siyuan-note) Fixed in 3.8.7

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-10-25
siyuan-note siyuan 3.8.7
6 records Highest priority Priority HIGH 1 HIGH, 3 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2026-80184 Cleartext transmission in SiYuan exposes login and session cookiesPriority HIGH 68
- TI-2026-80188 SQL injection in SiYuan history search exposes history.dbPriority MEDIUM 64
- TI-2026-80187 SiYuan Stored XSS via KaTeX \href in Math BlocksPriority MEDIUM 56
Show all 6 records →

Timeline

2026-10-25 Threatist record created from CVE-2026-116168
2026-10-26 Priority changed: MEDIUM → LOW
2026-10-27 Alias added: GHSA-659w-8mpv-qcqc
2026-11-04 CISA SSVC decision points changed
2026-11-04 Priority changed: LOW → MEDIUM

References

Advisory 1

GitHub Security Advisory (GHSA-q768-4j87-gf3w)

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