CVE-2026-44594: Esm-Dev Esm.sh

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

esm.sh is a no-build content delivery network (CDN) for web development. In 137 and earlier, a Local File Inclusion (LFI) vulnerability exists in the esbuild plugin's handling of the browser field in package.json. An attacker can publish an npm package that causes the server to read and return arbitrary files from the host filesystem during the build process.

Affected products

• Esm-Dev Esm.sh: up to and including 137

Published 2026-05-28. Last modified 2026-06-17.