{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "94d6a42a0362c0a6938a29ab84addb1fe0aca21c"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "original_tag": "v3.8.10",
                "range": [
                  {
                    "fixed": "be17ed1e0510bb6371cb8a162e16898a697fa118"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "94d6a42a0362c0a6938a29ab84addb1fe0aca21c"
            },
            {
              "fixed": "be17ed1e0510bb6371cb8a162e16898a697fa118"
            }
          ],
          "repo": "https://github.com/siyuan-note/siyuan",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-hq2c-hh95-vrr6"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-22"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126776.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "range": [
              {
                "introduced": "3.7.0"
              },
              {
                "fixed": "3.8.10"
              }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandardRange"
          }
        ]
      },
      {
        "extracted_events": [
          {
            "range": [
              {
                "introduced": "3.7.0"
              },
              {
                "fixed": "3.8.10"
              }
            ],
            "source": "CPE_FIELD",
            "strategy": "CPEApplicability"
          }
        ]
      },
      {
        "extracted_events": [
          {
            "range": [
              {
                "introduced": "3.7.0"
              },
              {
                "fixed": "3.8.10"
              }
            ],
            "source": "DESCRIPTION"
          }
        ]
      }
    ]
  },
  "details": "SiYuan 3.7.0 before 3.8.10 on Windows contains a path traversal vulnerability in kernel/util/webfetch.go that allows attackers to write files outside the import directory via backslash-encoded filenames. Attackers controlling a URL fetched by the MCP web_fetch or http_request tools can use %5C-encoded ..\\ sequences to write chosen response bytes to directories above temp/import that are writable by the SiYuan user.",
  "id": "CVE-2026-126776",
  "modified": "2026-11-13T02:30:57.560301882Z",
  "published": "2026-11-11T18:41:08.401Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126776.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/siyuan-note/siyuan/releases/tag/v3.8.10"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-hq2c-hh95-vrr6"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126776"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/siyuan-3.7.0-before-3.8.10-path-traversal-file-write-via-mcp-web-fetch"
    },
    {
      "type": "FIX",
      "url": "https://github.com/siyuan-note/siyuan/commit/94d6a42a0362c0a6938a29ab84addb1fe0aca21c"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/siyuan-note/siyuan"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/siyuan-note/siyuan/blob/v3.7.0/kernel/util/webfetch.go#L155"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "SiYuan 3.7.0 before 3.8.10 Path Traversal File Write via MCP web_fetch"
}