Server-side Request Forgery (SSRF) Affecting github.com/esm-dev/esm.sh/server package, versions <136.1
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-15366580
- published1 Mar 2026
- disclosed25 Feb 2026
- creditpoppo
Introduced: 25 Feb 2026
CVE-2026-27730 (opens in a new tab)How to fix?
Upgrade github.com/esm-dev/esm.sh/server to version 136.1 or higher.
Overview
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the /http(s) route handler. An attacker can access internal network resources and retrieve sensitive information by supplying a crafted domain that resolves to a loopback or private IP address, thereby bypassing hostname-based validation. This is only exploitable if the /http(s) route is exposed to untrusted users and internal services are reachable from the server's network environment.