TI-2026-58706 Aliases CVE-2026-85581 GHSA-4qv4-f447-c9m2

SiYuan before v3.8.2 Denial of Service via unauthenticated UI-process registration

MEDIUM 44CWE-770Published 2026-09-04 · Updated 2026-09-10

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00575 47th percentileScored 2026-11-07

Fix Fixed siyuan (siyuan-note): 3.8.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
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 3.8.2	3.8.2	Patch available	CNA

siyuan Vendorsiyuan-note Affected before 3.8.2 Fixed in 3.8.2 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 3.8.2

Fixed in the same release

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

Release · 2026-09-04
siyuan-note siyuan 3.8.2
7 records Highest priority Priority HIGH 2 HIGH, 4 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2026-58710 SiYuan before v3.8.2 Unbounded Memory Consumption via ControlConcurrencyPriority HIGH 77
- TI-2026-58709 SiYuan before v3.8.2 Denial of Service via Auth ThrottlePriority HIGH 77
- TI-2026-58707 SiYuan before v3.8.2 Unbounded Session Creation via Basic AuthPriority MEDIUM 64
Show all 7 records →

Timeline

2026-10-02 Threatist record created from CVE-2026-85581
2026-10-03 Alias added: GHSA-4qv4-f447-c9m2

References

Advisory 1

GitHub Security Advisory (GHSA-wv96-wmf5-xvj2)

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