MinIO has JWT Algorithm Confusion in OIDC Authentication in github.com/minio/minio (CVE-2026-33322) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-33322GHSA-5CX5-WH4M-82FH

MinIO has JWT Algorithm Confusion in OIDC Authentication in github.com/minio/minio

Answer in brief

CVE-2026-33322 records a Unknown severity vulnerability in MinIO has JWT Algorithm Confusion in OIDC Authentication in github.com/minio/minio. The current sources do not mark it as known exploited. The current feed maps github.com/minio/minio (go). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Mar 19, 2026Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Aug 7, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps github.com/minio/minio (go). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
github.com/minio/miniogo	>=0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for github.com/minio/minio.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Mar 19, 2026
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Aug 7, 2026

Sources and claim methodology

Upstream source description

### 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_20260317212516.0.0_amd64.deb](https://dl.min.io/aistor/minio/release/linux-amd64/minio_20260317212516.0.0_amd64.deb) | | DEB | arm64 | [minio_20260317212516.0.0_arm64.deb](https://dl.min.io/aistor/minio/release/linux-arm64/minio_20260317212516.0.0_arm64.deb) | | RPM | amd64 | [minio-20260317212516.0.0-1.x86_64.rpm](https://dl.min.io/aistor/minio/release/linux-amd64/minio-20260317212516.0.0-1.x86_64.rpm) | | RPM | arm64 | [minio-20260317212516.0.0-1.aarch64.rpm](https://dl.min.io/aistor/minio/release/linux-arm64/minio-20260317212516.0.0-1.aarch64.rpm) | ### Container Images ```bash # Standard docker pull quay.io/minio/aistor/minio:RELEASE.2026-03-17T21-25-16Z podman pull quay.io/minio/aistor/minio:RELEASE.2026-03-17T21-25-16Z # FIPS docker pull quay.io/minio/aistor/minio:RELEASE.2026-03-17T21-25-16Z.fips podman pull quay.io/minio/aistor/minio:RELEASE.2026-03-17T21-25-16Z.fips ``` ### Homebrew (macOS) ```bash brew install minio/aistor/minio ``` ### Workarounds - [Users of the open-source `minio/minio` project should upgrade to MinIO AIStor `RELEASE.2026-03-17T21-25-16Z` or later.](https://docs.min.io/enterprise/aistor-object-store/upgrade-aistor-server/community-edition/) - As a workaround, ensure that the OIDC `ClientSecret` is treated as a highly sensitive credential and is not exposed to untrusted parties.

Quoted source text, attributed separately from HOL analysis.