esm.sh CDN service has JS Template Literal Injection in CSS-to-JavaScript
Published Nov 19, 2025
9.6
CRITICALCVSS 3.1
EPSS 0.48%
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.
Affected products
-
- Version < 136StatusaffectedConstraints-
- Version
No data.
No Red Hat product state for this CVE.
github.com/esm-dev/esm.sh
Go
Introduced 0 Fixed 0.0.0-20251118065157-87d2f6497574
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| Go | github.com/esm-dev/esm.sh | 0 | 0.0.0-20251118065157-87d2f6497574 |
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
1 other source (GHSA) ▾
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
PoCAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Nov 20, 2025 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2025–2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.48% (0.00480) | 39.23th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.42% (0.00422) | 33.48th | v5 (v2026.06.15) |
| Nov 20, 2025 | 0.05% (0.00048) | 10.35th | v4 (v2025.03.14) |
References (4)
- https://github.com/advisories/GHSA-hcpf-qv9m-vfgp Advisory
- https://github.com/esm-dev/esm.sh/commit/87d2f6497574bf4448641a5527a3ac2beba5fd6c x_refsource_MISCPatch
- https://github.com/esm-dev/esm.sh/security/advisories/GHSA-hcpf-qv9m-vfgp exploitx_refsource_CONFIRMVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2025-65026
| Link | Providers | Tags |
|---|---|---|
| https://github.com/advisories/GHSA-hcpf-qv9m-vfgp | Advisory | |
| https://github.com/esm-dev/esm.sh/commit/87d2f6497574bf4448641a5527a3ac2beba5fd6c | x_refsource_MISCPatch | |
| https://github.com/esm-dev/esm.sh/security/advisories/GHSA-hcpf-qv9m-vfgp | exploitx_refsource_CONFIRMVendor Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2025-65026 |
Change history (0)
No recorded changes yet.