CVE-2026-44593

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

No CVSS.

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-05-28 16:16

Updated : 2026-06-17 10:51

NVD link : CVE-2026-44593

Mitre link : CVE-2026-44593

CVE.ORG link : CVE-2026-44593

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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