CVE-2026-23644: GO-2026-4332 - esm.sh has a path traversal in extractPackageTarball enables file writes from malicious packages

CVE-2026-23644 · Severity: medium · CVSS 4 · Published 2026-02-26

esm.sh has a path traversal in extractPackageTarball enables file writes from malicious packages

Technologies: github.com/esm-dev/esm.sh (Go). Vendors: Go.

Quick answers

Is CVE-2026-23644 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-23644 being exploited in the wild.
How severe is CVE-2026-23644?
Medium severity, with a CVSS score of 4, published 26 February 2026.
Which products and versions are affected?
github.com/esm-dev/esm.sh (Go) ECOSYSTEM:introduced=0.0.1,last_affected=136, SEMVER:introduced=0,fixed=0.0.0-20260116051925-c62ab83c589e.
Is there a fix for CVE-2026-23644?
Yes. github.com/esm-dev/esm.sh (Go): upgrade to 0.0.0-20260116051925-c62ab83c589e or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-23644?
Check whether you run github.com/esm-dev/esm.sh (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/esm-dev/esm.sh (Go): upgrade to 0.0.0-20260116051925-c62ab83c589e or later
    go get github.com/esm-dev/esm.sh@v0.0.0-20260116051925-c62ab83c589e

Affected products

  • github.com/esm-dev/esm.sh (Go) ECOSYSTEM:introduced=0.0.1,last_affected=136, SEMVER:introduced=0,fixed=0.0.0-20260116051925-c62ab83c589e

Identifiers

  • CVE-2026-23644
  • GHSA-2657-3c98-63jq
  • GO-2026-4332

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