CVE-2026-85581: Siyuan-Note Siyuan

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

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.

Affected products

• Siyuan-Note Siyuan: before 3.8.2 (fixed in 3.8.2)

Published 2026-09-04. Last modified 2026-09-10.