CVE-2025-65026
criticalesm.sh is a nobuild content delivery network(CDN) for modern web development.
Vendor / product: Esm — esm.sh
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:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Affected products
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
References
- https://github.com/esm-dev/esm.sh/commit/87d2f6497574bf4448641a5527a3ac2beba5fd6c security-advisories@github.com
- https://github.com/esm-dev/esm.sh/security/advisories/GHSA-hcpf-qv9m-vfgp security-advisories@github.com
- https://github.com/esm-dev/esm.sh/security/advisories/GHSA-hcpf-qv9m-vfgp 134c704f-9b21-4f2e-91b3-4a467353bcc0