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CVE-2026-33203

SiYuan has an Unauthenticated WebSocket DoS via Auth Keepalive Bypass

Published: Mar 20, 2026Updated: Mar 23, 2026 Sources: CVE List NVDCWE-248
7.5HIGH
NVD MITRE
EPSS Score
0.5%
Top 60.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

Description

SiYuan is a personal knowledge management system. Prior to version 3.6.2, the SiYuan kernel WebSocket server accepts unauthenticated connections when a specific "auth keepalive" query parameter is present. After connection, incoming messages are parsed using unchecked type assertions on attacker-controlled JSON. A remote attacker can send malformed messages that trigger a runtime panic, potentially crashing the kernel process and causing denial of service. Version 3.6.2 fixes the issue.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-248CWE-306

Affected Products

b3log
oss-project
siyuanOn-premWeb App
Web & CMS Plugins / cms-core
siyuan-note
commercial
siyuanOn-premDesktop App
Consumer Software / productivity

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3g9h-9hp4-654v
github.com

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