# CVE-2026-53970

## Summary

- **CVE ID:** CVE-2026-53970
- **Severity:** HIGH
- **CVSS Score:** 7.5 (CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-494
- **Published:** Aug 14, 2026
- **Last Modified:** Aug 18, 2026

## Description

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.

## Affected Products

- lucasgelfond — ZeroBrew (0)

## References

- [CNA](https://github.com/lucasgelfond/zerobrew)
- [CNA](https://github.com/lucasgelfond/zerobrew/commit/89a60b73c7edd6b662e2a085be3d981b6ebeb1aa)
- [CNA](https://www.vulncheck.com/advisories/zerobrew-version-and-prior-missing-checksum-verification-rce-via-shim-rb)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.17%
- **EPSS Percentile:** 6.6

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._