TI-2026-56987 Aliases CVE-2026-82649 GHSA-jrgp-6vq3-j6hp

SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path

HIGH 72CWE-427Published 2026-08-30 · Updated 2026-09-01

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-427.

Summary

SiYuan Windows installer before version 3.8.1 (affected versions >= 2.0.14) contains an uncontrolled search path element vulnerability in its NSIS installer, which invokes system executables such as TASKKILL by name rather than by absolute path. Because NSIS nsExec::Exec resolves these calls using a search path that includes the installer's own launch directory ahead of System32, an attacker who plants a malicious executable (e.g., a renamed TASKKILL.exe) in that directory can have it executed when the installer runs. These calls occur in electron-builder's preInit hook before the license page is displayed, and with an all-users (elevated) install the planted binary executes with an elevated token, resulting in local privilege escalation.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00173 6th percentileScored 2026-11-07

Fix Fixed siyuan (siyuan-note): 3.8.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Total

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	2.0.14 to before 3.8.1	3.8.1	Patch available	CNA

siyuan Vendorsiyuan-note Affected 2.0.14 to before 3.8.1 Fixed in 3.8.1 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

Fix · CNA siyuan (siyuan-note) Fixed in 3.8.1

Fixed in the same release

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

Release · 2026-08-30
siyuan-note siyuan 3.8.1
6 records Highest priority Priority HIGH 2 HIGH, 1 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2026-56991 SiYuan before v3.8.1 Stored XSS via confirmDialogPriority HIGH 75
- TI-2026-56992 SiYuan before v3.8.1 Stored XSS via block namePriority MEDIUM 42
- TI-2026-56990 SiYuan before v3.8.1 Information Disclosure via Publish AccessPriority LOW 36
Show all 6 records →

Timeline

2026-10-02 Threatist record created from CVE-2026-82649
2026-10-03 Alias added: GHSA-jrgp-6vq3-j6hp

References

Patch 1

Patch Commit

Advisory 1

GitHub Security Advisory (GHSA-9j65-967f-5rv3)

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