CVE-2026-1026577.5HighCWE-22

CVE-2026-102657: esm.sh: web.NewHandler allows arbitrary file read via encoded dot-segment path traversal

esm-dev · esm.sh

Affected: esm-dev esm.sh · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.7%probability of exploitation in the next 30 days

54th percentile

050100

Higher than 54% of scored CVEs

7.5HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

esm.sh is a no-build content delivery network (CDN) for web development. Prior to server version 137_7, the documented web.NewHandler static file server in web/handler.go joins the URL-decoded r.URL.Path with Config.AppDir without verifying that the result remains inside the configured application directory. URL-encoded dot segments such as %2e%2e bypass the plain traversal redirect performed by Go's ServeMux, allowing an unauthenticated remote attacker to make the server open and return files outside Config.AppDir that are readable by the server process. The confirmed impact is file disclosure only, and the issue is reachable with Dev disabled. This issue is fixed in server version 137_7.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

esm-dev · esm.sh< 137_7

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Path Traversal · File and Path Handling
Vendor: esm-dev
Published: November 2026
Band: Unlikely (under 1%), November 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-102657 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.