---
id: CVE-2026-80427
title: >-
  bestzip builds the argument list for the system zip utility without separating
  options from operands
summary: >-
  bestzip builds the argument list for the system zip utility without separating
  options from operands. The destination archive path and the caller-supplied
  source paths are passed to the child process with no -- delimiter between
  them, so…
severity: high
cvss: 8.4
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-88
published: '2026-08-26'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T20:43:32.537'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80427'
references:
  - url: 'https://github.com/nfriedly/node-bestzip'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/nfriedly/node-bestzip/security/advisories/GHSA-p87m-9567-rgcc
    label: disclosure@vulncheck.com
  - url: 'https://www.npmjs.com/package/bestzip'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/bestzip-before-2.2.6-and-3.0-x-before-3.0.2-argument-injection-via-missing-option-delimiter
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/nfriedly/node-bestzip/security/advisories/GHSA-p87m-9567-rgcc
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00223
epssPercentile: 0.11476
ingestedAt: '2026-09-24T20:51:40.231Z'
---

## Overview

bestzip builds the argument list for the system zip utility without separating options from operands. The destination archive path and the caller-supplied source paths are passed to the child process with no -- delimiter between them, so any source entry beginning with a hyphen is interpreted by zip as an option rather than a file name. zip accepts -T to test the finished archive and -TT to name the command used to perform that test, so a source list containing those two entries and a command string causes zip to run that command through a shell once the archive has been written. An application that passes a file name or path it received from an untrusted source into the bestzip API therefore executes a command of the supplier's choosing. Versions 2.2.6 and 3.0.2 add the delimiter.

## Remediation

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