FKIE_CVE-2026-33203

Vulnerability from fkie_nvd - Published: 2026-03-20 23:16 - Updated: 2026-03-23 18:48
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.
References
security-advisories@github.comhttps://github.com/siyuan-note/siyuan/security/advisories/GHSA-3g9h-9hp4-654vExploit, Vendor Advisory
Impacted products
Vendor Product Version
b3log siyuan *
To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "27CB71A7-7208-417A-AE6D-266D57F683E9",
              "versionEndExcluding": "3.6.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "SiYuan es un sistema de gesti\u00f3n de conocimiento personal. Antes de la versi\u00f3n 3.6.2, el servidor WebSocket del kernel de SiYuan acepta conexiones no autenticadas cuando un par\u00e1metro de consulta espec\u00edfico \u0027auth keepalive\u0027 est\u00e1 presente. Despu\u00e9s de la conexi\u00f3n, los mensajes entrantes se analizan utilizando aserciones de tipo no verificadas en JSON controlado por el atacante. Un atacante remoto puede enviar mensajes malformados que desencadenan un p\u00e1nico en tiempo de ejecuci\u00f3n, lo que podr\u00eda bloquear el proceso del kernel y causar una denegaci\u00f3n de servicio. La versi\u00f3n 3.6.2 corrige el problema."
    }
  ],
  "id": "CVE-2026-33203",
  "lastModified": "2026-03-23T18:48:43.490",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-20T23:16:45.520",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3g9h-9hp4-654v"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-248"
        },
        {
          "lang": "en",
          "value": "CWE-306"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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