CVSS 4.0
5.5 mediumCVSS: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:PCVE-2025-59342
Medium (5.5). EPSS 3.2% chance of exploitation in the next 30 days. Fixed in github.com/esm-dev/esm.sh 136.1.
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.
Severity
- EPSS
- 3.2% chance of exploitation in the next 30 days; higher than 87% of CVEs (scores of 2026-10-31)
- CWE
- CWE-24
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-g2h5-cvvr-7gmw | Go | github.com/esm-dev/esm.sh | <136.1 | 136.1 |
| GO-2025-3967 | Go | github.com/esm-dev/esm.sh | all versions | no fix published |