{"affected":[{"defaultStatus":"unaffected","ecosystem":"golang","packageName":"github.com/siyuan-note/siyuan/kernel","product":"siyuan","source":"CNA: VulnCheck","vendor":"siyuan-note","versions":[{"lessThan":"3.8.10","status":"affected","version":"3.7.0","versionType":"semver"},{"status":"unaffected","version":"3.8.10","versionType":"semver"}]}],"cveId":"CVE-2026-126776","cwes":["CWE-22"],"description":"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.","epss":null,"exploits":[],"kev":null,"metrics":[{"score":6,"severity":"medium","source":"CNA: VulnCheck","vector":"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","version":"4.0"},{"score":5.3,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N","version":"3.1"}],"modifiedAt":1794422468401,"publishedAt":1794422468401,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-hq2c-hh95-vrr6"},{"source":"CNA: VulnCheck","tags":["patch"],"url":"https://github.com/siyuan-note/siyuan/commit/94d6a42a0362c0a6938a29ab84addb1fe0aca21c"},{"source":"CNA: VulnCheck","tags":["release-notes"],"url":"https://github.com/siyuan-note/siyuan/releases/tag/v3.8.10"},{"source":"CNA: VulnCheck","tags":["technical-description"],"url":"https://github.com/siyuan-note/siyuan/blob/v3.7.0/kernel/util/webfetch.go#L155"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/siyuan-3.7.0-before-3.8.10-path-traversal-file-write-via-mcp-web-fetch"}],"remediation":[{"kind":"fix","source":"CNA: VulnCheck","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/siyuan-note/siyuan/commit/94d6a42a0362c0a6938a29ab84addb1fe0aca21c"}],"revision":"8f01779c802207f2eb454d8fe812ef8d3390f64e2a402703e958ad8a7b8099d3","sources":[{"modifiedAt":1794422468401,"name":"CNA: VulnCheck","retrievedAt":1794424134498,"url":"https://www.cve.org/CVERecord?id=CVE-2026-126776"}],"ssvc":null,"status":"published","title":"SiYuan 3.7.0 before 3.8.10 Path Traversal File Write via MCP web_fetch","updatedAt":1794424134498}