---
id: CVE-2026-122267
title: >-
  MinIO Signature V4 verification before RELEASE.2026-09-22T19-25-18Z accepts
  unsigned x-amz-* headers, letting a presigned PUT URL be escalated into a
  cross-bucket read.
summary: >-
  MinIO Signature V4 verification before RELEASE.2026-09-22T19-25-18Z accepts
  unsigned x-amz-* headers, letting a presigned PUT URL be escalated into a
  cross-bucket read.
severity: high
cvss: 8.8
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-347
vendor: Chainguard
product: MinIO
affected:
  - MinIO <= RELEASE.2026-09-21T00-15-41Z
published: '2026-11-05'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T22:00:11.719Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-122267'
references:
  - url: >-
      https://github.com/chainguard-forks/minio/security/advisories/GHSA-48rv-pgqh-mhjg
tags:
  - cve.org
ingestedAt: '2026-11-05T23:41:31.956Z'
epss: 0.00199
epssPercentile: 0.09743
---

## Overview

MinIO Signature V4 verification before RELEASE.2026-09-22T19-25-18Z accepts unsigned x-amz-* headers, letting a presigned PUT URL be escalated into a cross-bucket read.

## Affected

- `MinIO <= RELEASE.2026-09-21T00-15-41Z`

## Remediation

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