Esm.Sh
CVE-2026-23644
HIGH
GHSA-2657-3c98-63jq
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessCraft malicious tar archive with absolute paths
-
ExploitUpload to esm.sh CDN
-
Executionpath.Clean fails to sanitize absolute paths
-
ImpactOverwrite arbitrary files on server
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V5 - File Handling Path canonicalization, traversal prevention
MITRE ATT&CK
2 techniques across 2 tactics: Discovery, Collection The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | No special conditions — remote unauthenticated exploitation against esm.sh CDN versions prior to Go pseudoversion 0.0.0-20260116051925-c62ab83c589e that process tar archives with incomplete path sanitization. |
| Impact | CVSS 7.5 (HIGH). Attack vector: Network. Complexity: Low. Privileges required: None. User interaction: None. Exploitable via remote/network. Public exploit/POC available. |
| Exploit ScenarioDerived | A remote attacker could exploit this vulnerability to compromise the affected system. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Mar 12, 2026
Path traversal in esm.sh CDN prior to version 0.0.0-20260116051925-c62ab83c589e allows unauthenticated remote attackers to write arbitrary files to the server through malicious tar archives, bypassing incomplete path sanitization. Public exploit code exists for this vulnerability. The issue stems from improper validation of absolute paths in tar file entries, enabling potential code execution or service disruption on affected systems.
Earlier versions of this analysis (1)
esm.sh is a no-build content delivery network (CDN) for web development. Prior to Go pseeudoversion 0.0.0-20260116051925-c62ab83c589e, the software has a path traversal vulnerability due to an incomplete fix. [CVSS 7.5 HIGH]
RemediationAI
A vendor patch is available — apply it immediately. Validate and sanitize file path inputs. Use allowlists. Restrict network access to the affected service where possible.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in go
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Classified as CWE-22 (Path Traversal). Affects Esm.Sh. esm.sh is a no-build content delivery network (CDN) for web development. Prior to Go pseeudoversion 0.0.0-20260116051925-c62ab83c589e, the software has a path traversal vulnerability due to an incomplete fix. path.Clean normalizes a path but does not prevent absolute paths in a malicious tar file. Commit https://github.com/esm-dev/esm.sh/commit/9d77b88c320733ff6689d938d85d246a3af9af16, corresponding to pseudoversion 0.0.0-20260116051925-c62ab83c589e, fixes this issue.
Know when Esm.Sh gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Primary rating from GitHub Advisory.
CVSS VectorGitHub Advisory
Lifecycle Timeline
3DescriptionGitHub Advisory
esm.sh is a no-build content delivery network (CDN) for web development. Prior to Go pseeudoversion 0.0.0-20260116051925-c62ab83c589e, the software has a path traversal vulnerability due to an incomplete fix. path.Clean normalizes a path but does not prevent absolute paths in a malicious tar file. Commit https://github.com/esm-dev/esm.sh/commit/9d77b88c320733ff6689d938d85d246a3af9af16, corresponding to pseudoversion 0.0.0-20260116051925-c62ab83c589e, fixes this issue.
Executive ViewAI
Organizations using esm.sh face notable risk from CVE-2026-23644, a path traversal vulnerability rated CVSS 7.5. This could allow attackers to access or modify files outside intended directories, potentially exposing sensitive configuration or credentials. Proof-of-concept code is publicly available, increasing the risk of exploitation. A patch is available and should be applied as part of regular vulnerability management.
Apply vendor patch. If immediate patching is not feasible: (1) Restrict file upload functionality via WAF; (2) Implement allowlist-based file type validation; (3) Use chroot/containerization to limit filesystem access.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Path traversal exploits occur when applications use user-controlled input to construct file system paths without proper validation.
Affected Products (CPE)GitHub Advisory
esm.sh is a no-build content delivery network (CDN) for web development. In version 136, esm.sh is vulnerable to a full-
esm.sh versions up to 137 contain an SSRF vulnerability in the `/http(s)` fetch route that allows remote attackers to by
Same weakness CWE-22 – Path Traversal
View allSame technique Path Traversal
View allVendor StatusVendor
SUSE
Severity: High| Product | Status |
|---|---|
| openSUSE Leap 15.6 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP6 | Fixed |
| openSUSE Leap 15.5 | Fixed |
Exploit-DB