{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*",
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "3.6.4"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "CPE_RANGE"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "62eed37a3263e3816354beea4041d82419b92b9d"
            }
          ],
          "repo": "https://github.com/siyuan-note/siyuan",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-w95v-4h65-j455"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40107.json"
  },
  "details": "SiYuan is a personal knowledge management system. Prior to 3.6.4, SiYuan configures Mermaid.js with securityLevel: \"loose\" and htmlLabels: true. In this mode, \u003cimg\u003e tags with src attributes survive Mermaid's internal DOMPurify and land in SVG \u003cforeignObject\u003e blocks. The SVG is injected via innerHTML with no secondary sanitization. When a victim opens a note containing a malicious Mermaid diagram, the Electron client fetches the URL. On Windows, a protocol-relative URL (//attacker.com/image.png) resolves as a UNC path (\\\\attacker.com\\image.png). Windows attempts SMB authentication automatically, sending the victim's NTLMv2 hash to the attacker. This vulnerability is fixed in 3.6.4.",
  "id": "CVE-2026-40107",
  "modified": "2026-07-15T01:48:52.277571086Z",
  "published": "2026-04-09T21:03:58.572Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40107.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w95v-4h65-j455"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40107"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "SiYuan Affected by Zero-Click NTLM Hash Theft and Blind SSRF via Mermaid Diagram Rendering"
}