Arbitrary Code Injection Affecting github.com/esm-dev/esm.sh/server package, versions <137.0
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-GOLANG-GITHUBCOMESMDEVESMSHSERVER-14073033
- published21 Nov 2025
- disclosed19 Nov 2025
- creditpyozzi-toss
Introduced: 19 Nov 2025
CVE-2025-65026 (opens in a new tab)How to fix?
Upgrade github.com/esm-dev/esm.sh/server to version 137.0 or higher.
Overview
Affected versions of this package are vulnerable to Arbitrary Code Injection in the CSS-to-JavaScript module conversion feature. An attacker can execute arbitrary JavaScript code by injecting ${...} expressions into CSS files, which are then evaluated when the resulting JavaScript module is imported by victim applications.