Vulnerability in Esm-Dev Esm.sh
CVE-2025-59342
esm.sh is a nobuild content delivery network(CDN) for modern web development. In 136 and earlier, a path-traversal flaw in the handling of the X-Zone-Id HTTP header allows an attacker to cause the application to write files outside the intended storage location. The header value is used to build a filesystem path but is not properly canonicalized or restricted to the application’s storage base directory. As a result, supplying ../ sequences in X-Zone-Id causes files to be written to arbitrary directories. Version 136.1 contains a patch.
EPSS: 0.028 (85.2th percentile) — read the EPSS interpretation.
Affected products
- Esm-dev Esm.sh — versions <= 136
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2025-59342?
- CVE-2025-59342 is a vulnerability in Esm-Dev Esm.sh, classified under CWE-24. Published 2025-09-17.
- Is CVE-2025-59342 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.