GitHub Security Advisory: GHSA-5cx5-wh4m-82fh
Package: github.com/minio/minio (GO)
Severity: CRITICAL (CVSS 0.0)
CWE: CWE-287: Improper Authentication, CWE-327: Use of a Broken or Risky Cryptographic Algorithm
Vulnerable versions: <= 0.0.0[PII_REDACTED]1848-7aac2a2c5b7c
Patched in: unpatched

Summary: MinIO has JWT Algorithm Confusion in OIDC Authentication

Details:
### Impact
_What kind of vulnerability is it? Who is impacted?_

A JWT algorithm confusion vulnerability in MinIO's OpenID Connect authentication allows an attacker who knows the OIDC `ClientSecret` to forge arbitrary identity tokens and obtain S3 credentials with any policy, including `consoleAdmin`.

An attacker with knowledge of the OIDC `ClientSecret` can:

- Impersonate any user identity
- Obtain S3 credentials with any IAM policy, including `consoleAdmin`
- Access, modify, or delete any data in the MinIO deployment

The attack is deterministic (100% success rate, no race conditions).

#### Attack Prerequisites

The attacker must know the OIDC `ClientSecret`. While this is a shared credential (not a private key), it is more accessible than commonly assumed:

- CVE-2023-28432 previously leaked environment variables including `MINIO_IDENTITY_OPENID_CLIENT_SECRET`
- Client secrets are often present in frontend OAuth configurations, mobile app bundles, CI/CD pipelines, and shared configuration files
- In many organizations, the client secret is accessible to operators and engineers who should not be able to forge arbitrary identities


#### Affected Versions

All MinIO releases from `RELEASE.2022-11-08T05-27-07Z` through the final release of the `minio/minio` open-source project.

### Patches

**Fixed in:** MinIO AIStor `RELEASE.2026-03-17T21-25-16Z`

## Downloads

### Binary Downloads

| Platform | Architecture | Download                                                                    |
| -------- | ------------ | --------------------------------------------------------------------------- |
| Linux    | amd64        | [minio](https://dl.min.io/aistor/minio/release/linux-amd64/minio)           |
| Linux    | arm64        | [minio](https://dl.min.io/aistor/minio/release/linux-arm64/minio)           |
| macOS    | arm64        | [minio](https://dl.min.io/aistor/minio/release/darwin-arm64/minio)          |
| macOS    | amd64        | [minio](https://dl.min.io/aistor/minio/release/darwin-amd64/minio)          |
| Windows  | amd64        | [minio.exe](https://dl.min.io/aistor/minio/release/windows-amd64/minio.exe) |

### FIPS Binaries

| Platform | Architecture | Download                                                                    |
| -------- | ------------ | --------------------------------------------------------------------------- |
| Linux    | amd64        | [minio.fips](https://dl.min.io/aistor/minio/release/linux-amd64/minio.fips) |
| Linux    | arm64        | [minio.fips](https://dl.min.io/aistor/minio/release/linux-arm64/minio.fips) |

### Package Downloads

| Format | Architecture | Download                                                                                                                            |
| ------ | ------------ | ----------------------------------------------------------------------------------------------------------------------------------- |
| DEB    | amd64        | [minio_[PII_REDACTED]2516.0.0_amd64.d