adm-zip async decompression denial of service

Severity: high · CVSS 7.5 · Published 2026-09-29

The adm-zip library, used to read and extract ZIP files in Node.js applications, does not properly handle errors that occur during async decompression of ZIP entries. An attacker can supply a ZIP file with a corrupted compressed payload to crash the entire Node.js process, taking down the server and affecting all users—even those unrelated to the malicious request.

Technologies: adm-zip (npm). Vendors: npm.

Quick answers

Is This vulnerability exploited in the wild?
No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?
High severity, with a CVSS score of 7.5, published 29 September 2026.
Which products and versions are affected?
adm-zip (npm) <= 0.6.0; Rg-Adguard Adm-Zip 0.6.0 and likely earlier versions; patched in 0.6.1.
Is there a fix for This vulnerability?
A patch was published on 2026-09-29: Version 0.6.1 released with error handler on inflateAsync stream Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?
It is attacked over the network, in a software library.
Am I affected?
Check whether you run adm-zip (npm) or Rg-Adguard Adm-Zip 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.

Technical details

The inflateAsync function in methods/inflater.js creates a zlib.createInflateRaw stream but fails to register an 'error' event listener. When zlib emits an error (e.g., Z_DATA_ERROR from malformed DEFLATE bytes), Node.js rethrows it as an uncaught exception on a later event loop tick, outside any try/catch that wraps the calling code. This affects all public async APIs: readFileAsync, readAsTextAsync, extractAllToAsync, and ZipEntry.getDataAsync. A fix is available in version 0.6.1.

Affected products

  • rg-adguard adm-zip 0.6.0 and likely earlier versions; patched in 0.6.1

Timeline

  • 2026-09-29: disclosed
  • 2026-09-29: patched: Version 0.6.1 released with error handler on inflateAsync stream

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