CVE-2026-33322 MinIO: JWT Algorithm Confusion in OIDC Authentication

Critical 9.2 Published 24 Mar 2026 Updated 25 Mar 2026

An attacker with the OIDC ClientSecret can forge identity tokens to gain full administrative access to the MinIO object storage system.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-33322?

CVE-2026-33322 is a critical authentication bypass vulnerability in minio, published on 24 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

MinIO is a high-performance object storage system. From RELEASE.2022-11-08T05-27-07Z to before RELEASE.2026-03-17T21-25-16Z, 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. This issue has been patched in RELEASE.2026-03-17T21-25-16Z.

Weakness: CWE-287

Which versions are affected by CVE-2026-33322?

3 open source packages ship an affected version, including github.com/minio/minio. It affects 1 product.

Package	Affected	Fixed in
`github.com/minio/minio` Go	All versions	None
`github.com/minio/minio` Go	All versions to `0.0.0-20260212201848-7aac2a2c5b7c`	None
`github.com/minio/minio` Go	All versions to `0.0.0-20260212201848-7aac2a2c5b7c`	None

Products include Minio Minio.

How do I fix CVE-2026-33322?

Upgrade to a fixed version.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-33322 being exploited?

There is no known exploitation of CVE-2026-33322 in the wild and no public exploit code.

Sources

Also known as GHSA-5cx5-wh4m-82fh, GO-2026-4779.