CVE-2025-59342mediumCWE-24

CVE-2025-59342: medium-severity vulnerability in esm-dev esm.sh

esm.sh writes arbitrary files via path traversal in `X-Zone-Id` header

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48Vexday Risk Score

Patch soon. It has a working public exploit.

ssvc Attendcvss 5.5epss 3.2%
from disclosure to weapon1 day
Published on NVDSep 17
1st PoC+1d
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
Affected products
esm-dev · esm.sh
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — esm-dev esm.sh

In the same product, most dangerous first.

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