CVE-2026-33203

Summary

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.

Affected Software

VendorProductVersion RangeStatus
siyuan-notesiyuan< 3.6.2affected

Weaknesses

  • CWE-248: CWE-248: Uncaught Exception
  • CWE-306: CWE-306: Missing Authentication for Critical Function

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: yes
    • Technical Impact: partial

References