CVE-2026-23644 json
esm.sh has path traversal in `extractPackageTarball` that enables file writes from malicious packages
published 2026-01-18 9 mo ago modified 2026-09-10 1 mo ago also EUVD-2026-3402 , GHSA-2657-3c98-63jq , GO-2026-4332
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- go github.com/esm-dev/esm.sh 0.0.0-20260116051925-c62ab83c589e
- esm esm.sh 0.0.0-20260116051925-c62ab83c589e
- govulncheck-vulndb openSUSE Leap 15.6 0.0.20260226T182644-150000.1.149.1
suse advisories SUSE-SU-2026:0757-1
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 9 mo ago
Exploit prediction
0.56% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- pkg.go.dev https://pkg.go.dev/vuln/GO-2025-4138 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P |
| CNA | 4.0 | 7.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/esm-dev/esm.sh | >=0.0.1, <=136 <0.0.0-20260116051925-c62ab83c589e |
0.0.0-20260116051925-c62ab83c589e |
Affected products
- esm-dev esm.sh
Classification
- Weakness
-
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory
References
-
github.com
/esm-dev/esm.sh/commit/9d77b88c320733ff6689d938d85d246a3af9af16
web, patch
-
github.com
/esm-dev/esm.sh/commit/c62ab83c589e7b421a0e1376d2a00a4e48161093
web, patch
-
pkg.go.dev
/vuln/GO-2025-4138
web, exploit, vendor-advisory
-
github.com
/esm-dev/esm.sh/security/advisories/GHSA-2657-3c98-63jq
web, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-23644
advisory
-
github.com
/esm-dev/esm.sh
package
-
pkg.go.dev
/vuln/GO-2026-4332
web
Sources
- CVE List CVE-2026-23644
- GitHub Advisory GHSA-2657-3c98-63jq
- NVD CVE-2026-23644
- OSV GO-2026-4332
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.