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CVE-2026-33203

Estado: AnalizadaAlta (7.5)—

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.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

AV:N/PR:N permite explotación remota sin autenticación (T1190). Vulnerabilidad en parsing de JSON causa panic/crash (T1499.004 DoS). El parámetro 'auth keepalive' sugiere debilidad de autenticación (T1078 secundario, confianza moderada).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account ManagementFilter Network TrafficApplication Developer GuidanceActive Directory ConfigurationVulnerability ScanningUser Training

Tecnologías afectadas (1)

B3log — Siyuan

CWE

Referencias

JSON original (NVD)

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