{"id":"CVE-2026-100637","aliases":["EUVD-2026-87731","GHSA-4fq5-2r2r-5cw9","GHSA-jhmh-hr4g-c5g2"],"status":"published","title":"SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID","description":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.","severity":{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00553,"percentile":0.4671,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-73"],"published":"2026-09-26T13:23:11Z","modified":"2026-10-28T02:30:55Z","products":[{"vendor":"siyuan-note","product":"siyuan"}],"references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2","tags":["vendor-advisory","exploit","advisory"]},{"url":"https://www.vulncheck.com/advisories/siyuan-before-3.8.4-path-traversal-via-checkoutrepo-sessionid","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-100637","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-4fq5-2r2r-5cw9"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100637.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-100637","title":"SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID","description":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.","status":"published","published":"2026-09-26T13:23:11.226Z","modified":"2026-10-05T15:06:34.28Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L","level":"high","assessor":"cna"},{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L","level":"high","assessor":"cna"}],"cwes":["CWE-73"],"updated_at":"2026-11-02T14:20:06.925367Z"}],"euvd":[{"id":"EUVD-2026-87731","description":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.","status":"published","published":"2026-09-26T13:23:11Z","modified":"2026-10-05T15:06:34Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L","level":"high"}],"updated_at":"2026-11-02T17:27:39.819382Z"}],"ghsa":[{"id":"GHSA-4fq5-2r2r-5cw9","title":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint...","description":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.","status":"published","published":"2026-09-26T15:31:16Z","modified":"2026-09-26T15:31:22Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L","level":"high"}],"cwes":["CWE-73"],"updated_at":"2026-11-02T15:12:30.047516Z"}],"nvd":[{"id":"CVE-2026-100637","description":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.","status":"published","published":"2026-09-26T14:16:45.32Z","modified":"2026-10-05T16:17:03.717Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L","level":"high","assessor":"secondary"}],"cwes":["CWE-73"],"updated_at":"2026-11-02T14:12:52.081323Z"}],"osv":[{"id":"CVE-2026-100637","title":"SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID","description":"SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.","status":"published","published":"2026-09-26T13:23:11.226Z","modified":"2026-10-28T02:30:55.051002705Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L","level":"high"}],"cwes":["CWE-73"],"updated_at":"2026-11-02T15:44:53.490346Z"}]}}