adm-zip: Decompression-bomb protection (fix for CVE-2026-39244) can be bypassed by declaring uncompressed size as 0 — GHSA-RCW4-F5RP-G42V

Summary

**Affected package:** adm-zip (npm) **Affected version:** 0.6.0 ## Summary The fix shipped for CVE-2026-39244 (`methods/inflater.js`) caps zlib's decompression output via `maxOutputLength: expectedLength`, where `expectedLength` is read directly from the ZIP entry's attacker-controlled "uncompressed size" header field (`CENLEN`/`LOCLEN`). This cap is only applied when `expectedLength > 0`: ```js const option =…

Timeline

Published by source

2026-09-29

Risk context

• Reported severity or threat level: high.
• Reported CVSS score: 7.5 out of 10.
• Review exposure for the affected product or family: npm: adm-zip.

Product

npm: adm-zip

What to do

General, cautious steps (verify details in the official source):

• Prioritize patching or mitigation immediately (treat as actively risky).
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source

Evidence and provenance

Canonical advisory ID

GHSA-RCW4-F5RP-G42V

Source

GitHub

Vendor

GitHub

Published by source

2026-09-29

Last source activity

2026-09-29

Curated by

hlukh.ch

Related advisories and connections

These advisories are connected by shared CVE, product, vendor, source, or time signals.