CVE-2026-44593 (GCVE-0-2026-44593)

Vulnerability from cvelistv5 – Published: 2026-05-28 14:44 – Updated: 2026-06-02 15:01
VLAI
Title
esm.sh: Legacy Route Path Traversal Can Lead to RCE
Summary
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.
Severity
8.7 (High)
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
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-02 15:00 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7868 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
esm-dev esm.sh Affected: <= 137
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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