---
id: CVE-2026-114104
title: adm-zip before 0.6.1 Duplicate ZIP Entry Name Validation Bypass
summary: >-
  adm-zip before 0.6.1 contains an inconsistent entry resolution vulnerability
  that allows attackers to bypass content validation by supplying ZIP archives
  with duplicate entry names. Attackers can craft archives where getEntry()
  returns t…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-436
vendor: cthackers
product: adm-zip
affected:
  - adm-zip < 0.6.1
published: '2026-10-21'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T00:37:05.291Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-114104'
references:
  - url: >-
      https://github.com/cthackers/adm-zip/security/advisories/GHSA-p634-w6r4-rjp2
    label: GitHub Security Advisory (GHSA-p634-w6r4-rjp2)
  - url: >-
      https://www.vulncheck.com/advisories/adm-zip-before-0.6.1-duplicate-zip-entry-name-validation-bypass
    label: >-
      VulnCheck Advisory: adm-zip before 0.6.1 Duplicate ZIP Entry Name
      Validation Bypass
tags:
  - cve.org
ingestedAt: '2026-10-21T01:37:08.014Z'
---

## Overview

adm-zip before 0.6.1 contains an inconsistent entry resolution vulnerability that allows attackers to bypass content validation by supplying ZIP archives with duplicate entry names. Attackers can craft archives where getEntry() returns the last duplicate while extractAllTo() writes the first, causing unvalidated bytes to be written to disk.

## Affected

- `adm-zip < 0.6.1`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.