Unauthenticated WebSocket Vulnerability in SiYuan Knowledge Management System
CVE-2026-33203

7.5HIGH

Key Information:

Vendor

Siyuan-note

Status
Siyuan
Vendor
CVE Published:
20 March 2026

What is CVE-2026-33203?

The SiYuan knowledge management system possesses a vulnerability in its WebSocket server, which allows unauthenticated connections due to a specific query parameter. This flaw enables remote attackers to send malformed JSON messages that, when processed, can lead to runtime errors and crashes, resulting in a denial of service. This issue is addressed in version 3.6.2, making an upgrade essential for maintaining system integrity.

Affected Version(s)

siyuan < 3.6.2

References

https://github.com/siyuan-note/siyuan/security/advisories...
x_refsource_CONFIRM

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.