CVE-2026-39244

HIGHPre-NVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-10. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this weekElevated
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

adm-zip before 0.5.18 is vulnerable to denial of service via a crafted ZIP file with a manipulated uncompressed size header field. In zipEntry.js line 103, Buffer.alloc(_centralHeader.size) allocates memory based on the declared uncompressed size from the ZIP central directory header without validating it against the actual compressed data size or imposing any upper bound. The size value is read directly from the binary header at entryHeader.js line 266 with no bounds check. An attacker can craft a ~120-byte ZIP file that declares ~4GB uncompressed size, causing a memory allocation amplification ratio of over 33 million to 1. The allocation occurs before CRC validation, so the malicious payload cannot be rejected early. All extraction and read methods are affected: readFile(), readAsText(), extractEntryTo(), extractAllTo(), extractAllToAsync(), test(), and entry.getData(). Any application accepting untrusted ZIP files via adm-zip is vulnerable to immediate process crash.

CVSS v3
7.5
EG Score
7.5(high)
EG Risk
65(Attend)
EG Risk 65/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
35.3%
KEV
Not listed

Published

July 10, 2026

Last Modified

July 10, 2026

Advisory Details (2)

Auto-updated Jul 10, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

[CVE-2026-39244] Denial of service via unbounded Buffer.alloc from crafted uncompressed-size header · Issue #568 · cthackers/adm-zip · GitHub

https://github.com/cthackers/adm-zip/issues/568
generic

GitHub - cthackers/adm-zip: A Javascript implementation of zip for nodejs. Allows user to create or extract zip files both in memory or to/from disk · GitHub

https://github.com/cthackers/adm-zip

Vendor Advisories for CVE-2026-39244(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
adm-zip—0.6.0—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 12× in last 7d / 31× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-23 14:18 UTCEPSS rescore
  2. 2026-07-23 14:18 UTCEPSS rescore
  3. 2026-07-23 03:10 UTCEG score recompute
  4. 2026-07-22 14:08 UTCEPSS rescore
  5. 2026-07-21 15:24 UTCEPSS rescore
  6. 2026-07-20 17:08 UTCEPSS rescore
  7. 2026-07-19 14:31 UTCEPSS rescore
  8. 2026-07-19 02:29 UTCEPSS rescore
  9. 2026-07-18 10:04 UTCEPSS rescore
  10. 2026-07-17 04:31 UTCGHSA enrichment
  11. 2026-07-16 17:28 UTCGHSA enrichment
  12. 2026-07-16 17:03 UTCEPSS rescore
  13. 2026-07-16 06:24 UTCGHSA enrichment
  14. 2026-07-15 19:20 UTCGHSA enrichment
  15. 2026-07-15 16:57 UTCEPSS rescore
  16. 2026-07-15 16:57 UTCEPSS rescore
  17. 2026-07-15 08:17 UTCGHSA enrichment
  18. 2026-07-15 02:00 UTCEPSS rescore
  19. 2026-07-14 21:14 UTCGHSA enrichment
  20. 2026-07-14 10:10 UTCGHSA enrichment
  21. 2026-07-13 23:07 UTCGHSA enrichment
  22. 2026-07-13 22:30 UTCEPSS rescore
  23. 2026-07-13 12:04 UTCEG score recompute▲ 7.50
  24. 2026-07-13 12:04 UTCGHSA enrichment
  25. 2026-07-13 06:13 UTCEPSS rescore
Show 6 more
  1. 2026-07-13 06:13 UTCEPSS rescore
  2. 2026-07-12 05:46 UTCEPSS rescore
  3. 2026-07-10 18:22 UTCMITRE cvelistV5CVSS v3 → 7.5 · severity → HIGH
  4. 2026-07-10 18:19 UTCNVD update
  5. 2026-07-10 16:33 UTCEG score recompute
  6. 2026-07-10 16:32 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-39244?
CVE-2026-39244 is a high vulnerability published on July 10, 2026. adm-zip before 0.5.18 is vulnerable to denial of service via a crafted ZIP file with a manipulated uncompressed size header field. In zipEntry.js line 103, Buffer.alloc(_centralHeader.size) allocates memory based on the declared uncompressed size from the ZIP central directory header without…
When was CVE-2026-39244 disclosed?
CVE-2026-39244 was first published in the National Vulnerability Database on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-39244 actively exploited?
CVE-2026-39244 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 35.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-39244?
CVE-2026-39244 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-39244?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-39244, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-39244

Explore →

Is Your Infrastructure Affected by CVE-2026-39244?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs