{"cve":"CVE-2026-44593","nvd":{"published":"2026-05-28T16:16:24.587","modified":"2026-10-26T11:10:00.157","status":"Deferred","description":"esm.sh is a no-build content delivery network (CDN) for web development. In 137 and earlier, the legacy router first retrieves a response from legacyServer, parses the incoming request path, and ultimately writes the data to storage via buildStorage.Put. The router concatenates the path components without sanitizing them, producing a storage key. When this key is used, the underlying file system resolves the relative segments and writes the file to the specified path. Thus an attacker can craft a request that writes data to arbitrary locations on the server.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","score":8.7},"cvss_v3":null,"cwes":["CWE-22"],"references":["https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465","https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465"],"products":[],"source":"nvd","synced_at":"2026-10-26T11:33:08.859761529+00:00"},"epss":{"cve":"CVE-2026-44593","score":0.00362,"percentile":0.2977,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-3636-h3vx-6465","url":"https://osv.dev/vulnerability/GHSA-3636-h3vx-6465","summary":"esm.sh: Legacy Route Path Traversal Can Lead to RCE","modified":"2026-06-25T18:56:35.298468646Z","packages":[{"ecosystem":"Go","name":"github.com/esm-dev/esm.sh","purl":"pkg:golang/github.com/esm-dev/esm.sh","ranges":["<0.0.0-20260508100112-1960055e1d53"],"fixed":["0.0.0-20260508100112-1960055e1d53"]}]},{"id":"GO-2026-5071","url":"https://osv.dev/vulnerability/GO-2026-5071","summary":"esm.sh: Legacy Route Path Traversal Can Lead to RCE in github.com/esm-dev/esm.sh","modified":"2026-06-25T18:45:15.015056267Z","packages":[{"ecosystem":"Go","name":"github.com/esm-dev/esm.sh","purl":"pkg:golang/github.com/esm-dev/esm.sh","ranges":["<0.0.0-20260508100112-1960055e1d53"],"fixed":["0.0.0-20260508100112-1960055e1d53"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}