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.

The following products are affected by CVE-2025-59342 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-59342.

URL	Resource
https://github.com/esm-dev/esm.sh/blob/main/server/router.go#L116
https://github.com/esm-dev/esm.sh/blob/main/server/router.go#L411
https://github.com/esm-dev/esm.sh/commit/833a29f42aeb0acbd7089a71be11dd0a292d3151
https://github.com/esm-dev/esm.sh/security/advisories/GHSA-g2h5-cvvr-7gmw