{"schemaVersion":3,"id":"CVE-2026-33203","aliases":["GHSA-3g9h-9hp4-654v","GO-2026-4752"],"status":"published","duplicateOf":null,"title":null,"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. 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