CVE-2026-32815

HIGH

SiYuan: Cross-Origin WebSocket Hijacking via Authentication Bypass — Unauthenticated Information Disclosure

Title source: cna
STIX 2.1

Description

SiYuan is a personal knowledge management system. In versions 3.6.0 and below, the WebSocket endpoint (/ws) allows unauthenticated connections when specific URL parameters are provided (?app=siyuan&id=auth&type=auth). This bypass, intended for the login page to keep the kernel alive, allows any external client — including malicious websites via cross-origin WebSocket — to connect and receive all server push events in real-time. These events leak sensitive document metadata including document titles, notebook names, file paths, and all CRUD operations performed by authenticated users. Combined with the absence of Origin header validation, a malicious website can silently connect to a victim's local SiYuan instance and monitor their note-taking activity. This issue has been fixed in version 3.6.1.

Scores

CVSS v3 7.5
EPSS 0.0036
EPSS Percentile 28.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-287
Status published
Products (3)
b3log/siyuan < 3.6.1
siyuan-note/siyuan 0Go
siyuan-note/siyuan < 3.6.1
Published Mar 19, 2026
Tracked Since Mar 20, 2026