---
id: CVE-2026-53970
title: >-
  ZeroBrew version 0.3.1 and prior contains a missing integrity verification
  vulnerability in the Ruby compatibility shim that allows network attackers to
  execute arbitrary code by substituting malicious content at formula resource
  or URL-…
summary: >-
  ZeroBrew version 0.3.1 and prior contains a missing integrity verification
  vulnerability in the Ruby compatibility shim that allows network attackers to
  execute arbitrary code by substituting malicious content at formula resource
  or URL-…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-494
published: '2026-08-14'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T20:06:30.133'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53970'
references:
  - url: 'https://github.com/lucasgelfond/zerobrew'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/lucasgelfond/zerobrew/commit/89a60b73c7edd6b662e2a085be3d981b6ebeb1aa
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/zerobrew-version-and-prior-missing-checksum-verification-rce-via-shim-rb
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00254
epssPercentile: 0.15137
ingestedAt: '2026-09-24T20:51:40.202Z'
---

## Overview

ZeroBrew version 0.3.1 and prior contains a missing integrity verification vulnerability in the Ruby compatibility shim that allows network attackers to execute arbitrary code by substituting malicious content at formula resource or URL-based patch URLs without checksum validation. Attackers can intercept or replace downloads for secondary resource and patch paths in shim.rb, injecting attacker-controlled build steps or source tree modifications that execute during source builds via 'zb install --build-from-source' without any integrity warning.

## Remediation

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