Vulnerability in Lucasgelfond Zerobrew
CVE-2026-53970
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (15.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Lucasgelfond Zerobrew — versions 0
Weakness classification (CWE)
References
- github.com/lucasgelfond/zerobrew (issue-tracking)
- github.com/lucasgelfond/zerobrew/commit/89a60b73c7edd6b662e2a085be3d981b6ebeb1aa (patch)
- www.vulncheck.com/advisories/zerobrew-version-and-prior-missing-checksum-verifi… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-53970?
- CVE-2026-53970 is a high-severity vulnerability in Lucasgelfond Zerobrew, classified under Download of Code Without Integrity Check. CVSS score: 7.5/10. Published 2026-08-14.
- How severe is CVE-2026-53970?
- High severity. CVSS v3 base score is 7.5 out of 10.