CVE-2025-65026

CRITICAL EPSS 35.0%
Published Nov 19, 20257mo ago · Modified Jun 17, 20262w ago
9.6 CVSS 3.1
Critical
Find Similar
Published Nov 19, 2025 7mo ago
Last Modified Jun 17, 2026 2w ago

Description

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 Details

Base Score
9.6
Exploitability
2.8
Impact
6.0
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction Required
Scope Changed
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
35.0% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 2

CWE-79 Cross-site Scripting Injection
CWE-94 Improper Control of Generation of Code (Code Injection) Injection

Affected Products 1

VendorProductVersionRange
esmesm.sh* <136

References 2

  • github.com https://github.com/esm-dev/esm.sh/commit/87d2f6497574bf4448641a5527a3ac2beba5fd6c
    Patch
  • github.com https://github.com/esm-dev/esm.sh/security/advisories/GHSA-hcpf-qv9m-vfgp
    ExploitVendor Advisory

Remediation

  • github.com https://github.com/esm-dev/esm.sh/commit/87d2f6497574bf4448641a5527a3ac2beba5fd6c
    Patch