CVE-2026-44593 Details
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.
A path traversal vulnerability has been identified in esm.sh, a no-build content delivery network for web development, affecting versions prior to 137. The issue arises in the legacy router, which concatenates request path components into a storage key without proper sanitization. This key is then used to write data to the file system, allowing attackers to manipulate the path and overwrite files in arbitrary locations on the server. Exploitation of this vulnerability could lead to privilege escalation and remote code execution by overwriting critical binaries or scripts.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed May 28, 2026CISA-ADP
Assessed Jun 2, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465 | CISA-ADP | AdvisoryExploitVendor |
| https://github.com/esm-dev/esm.sh/security/advisories/GHSA-3636-h3vx-6465 | [email protected] | AdvisoryExploitVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-22 | Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| esm.sh | < v137 |
CPE
Remediation
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Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Jun 2, 2026 | CVE Modified | CISA-ADP |
| May 28, 2026 | New CVE Received | [email protected] |