CVE-2026-44594: high-severity vulnerability in esm-dev esm.sh
esm.sh: Path Traversal via package.json browser field allows reading arbitrary server files
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.4%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
esm-dev · esm.shRelated CVEs — esm-dev esm.sh
In the same product, most dangerous first.
CVE-2025-59342MEDIUMesm.sh writes arbitrary files via path traversal in `X-Zone-Id` headerEPSS 3.2%CVE-2025-59341HIGHLocal File Inclusion in esm.shEPSS 1.6%CVE-2026-102657HIGHesm.sh: web.NewHandler allows arbitrary file read via encoded dot-segment path traversalEPSS 0.7%CVE-2025-65025HIGHesm.sh CDN service has arbitrary file write via tarslipEPSS 0.6%CVE-2026-23644HIGHesm.sh has path traversal in `extractPackageTarball` that enables file writes from malicious packagesEPSS 0.6%CVE-2025-65026MEDIUMesm.sh CDN service has JS Template Literal Injection in CSS-to-JavaScriptEPSS 0.5%