Medium 6.1Published Nov 19, 2025

CVE-2025-65026esm.sh CDN service has JS Template Literal Injection in CSS-to-JavaScript

Updated under an hour ago (Oct 26, 2026, 9:10 AM ET)

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It affects esm-dev esm.sh and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for esm-dev esm.sh

Exploited in the last 30 days

esm.sh is a nobuild content delivery network(CDN) for modern web development. Prior to version 136, The esm.sh CDN service contains a Template Literal Injection vulnerability (CWE-94) in its CSS-to-JavaScript module conversion feature. When a CSS file is requested with the ?module query parameter, esm.sh converts it to a JavaScript module by embedding the CSS content directly into a template literal without proper sanitization. An attacker can inject malicious JavaScript code using ${...} expressions within CSS files, which will execute when the module is imported by victim applications. This enables Cross-Site Scripting (XSS) in browsers and Remote Code Execution (RCE) in Electron applications. This issue has been patched in version 136.

CVSS: 6.1 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-94
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Nov 20, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

esm-dev esm.sh esm_dev:esm.sh (from the name)	before 136	CNA record
esm esm.sh esm:esm.sh	before 136	NVD

References

https://github.com/esm-dev/esm.sh/security/advisories/GHSA-hcpf-qv9m-vfgpx-refsource-confirm, exploit, vendor-advisory
https://github.com/esm-dev/esm.sh/commit/87d2f6497574bf4448641a5527a3ac2beba5fd6cx-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.