CVE-2026-114105: Adm-zip incorrect permission assignment with keepOriginalPermission

CVE-2026-114105 · Severity: medium · CVSS 6.2 · Published 2026-10-21

Adm-zip is a JavaScript library for extracting and manipulating ZIP archives. When the keepOriginalPermission option is enabled, attackers can craft malicious ZIP files to set setuid or setgid bits on extracted files, allowing attacker-controlled executables to run with elevated privileges when extracted as root (such as in CI pipelines or container builds) and later executed.

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

Quick answers

Is CVE-2026-114105 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-114105 being exploited in the wild.
How severe is CVE-2026-114105?
Medium severity, with a CVSS score of 6.2, published 21 October 2026.
Which products and versions are affected?
adm-zip (npm) before 0.6.1.
Is there a fix for CVE-2026-114105?
Yes: fixed in adm-zip 0.6.1. Until then: Do not use keepOriginalPermission: true when extracting untrusted or attacker-influenced ZIP archives. Extract only trusted archives, or rely on the default behavior (keepOriginalPermission: false) which applies safe permission modes. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-114105 attacked?
It is attacked with local access.
Am I affected by CVE-2026-114105?
Check whether you run adm-zip (npm) 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.

How to fix

  • Fixed in: adm-zip 0.6.1

Do not use keepOriginalPermission: true when extracting untrusted or attacker-influenced ZIP archives. Extract only trusted archives, or rely on the default behavior (keepOriginalPermission: false) which applies safe permission modes.

Technical details

The vulnerability is an incorrect permission assignment (CWE-732) in the fileAttr getter, which uses a 12-bit mask (0xfff / 07777 octal) that preserves setuid (04000), setgid (02000), and sticky bits when reading from zip external file attributes. These attacker-controlled permission bits flow unmodified into chmod/chmodSync with no additional masking. The issue affects extractAllTo, extractAllToAsync, and extractEntryTo when keepOriginalPermission is true; extraction without this flag (the default) is not affected.

Affected products

  • npm adm-zip before 0.6.1

Timeline

  • 2026-09-11: disclosed
  • 2026-10-21: advisory

References

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