Allowed DELETE on resources on object locked buckets under Governance mode in Minio

Minio is a Multi-Cloud Object Storage framework. Affected versions do not correctly honor a `Deny` policy on ByPassGoverance. Ideally, minio should return "Access Denied" to all users attempting to DELETE a versionId with the special header `X-Amz-Bypass-Governance-Retention: true`. However, this was not honored instead the request will be honored and an object under governance would be incorrectly deleted. All users are advised to upgrade. There are no known workarounds for this issue.

Minio vulnerable to denial of access by an admin privileged user for root credential

Minio is a Multi-Cloud Object Storage framework. Starting with RELEASE.2020-12-23T02-24-12Z and prior to RELEASE.2023-03-13T19-46-17Z, a user with `consoleAdmin` permissions can potentially create a user that matches the root credential `accessKey`. Once this user is created successfully, the root credential ceases to work appropriately. The issue is patched in RELEASE.2023-03-13T19-46-17Z. There are ways to work around this via adding higher privileges to the disabled root user via `mc admin policy set`.

Minio Privilege Escalation on Windows via Path separator manipulation

Minio is a Multi-Cloud Object Storage framework. All users on Windows prior to version RELEASE.2023-03-20T20-16-18Z are impacted. MinIO fails to filter the `\` character, which allows for arbitrary object placement across buckets. As a result, a user with low privileges, such as an access key, service account, or STS credential, which only has permission to `PutObject` in a specific bucket, can create an admin user. This issue is patched in RELEASE.2023-03-20T20-16-18Z. There are no known workarounds.

Minio console object names with RIGHT-TO-LEFT OVERRIDE unicode character can be exploited

Minio Console is the UI for MinIO Object Storage. Unicode RIGHT-TO-LEFT OVERRIDE characters can be used to mask the original filename. This issue has been patched in version 0.28.0.

MinIO unsafe default: Access keys inherit `admin` of root user, allowing privilege escalation

MinIO is a High Performance Object Storage. When someone creates an access key, it inherits the permissions of the parent key. Not only for `s3:*` actions, but also `admin:*` actions. Which means unless somewhere above in the access-key hierarchy, the `admin` rights are denied, access keys will be able to simply override their own `s3` permissions to something more permissive. The vulnerability is fixed in RELEASE.2024-01-31T20-20-33Z.

User privilege escalation in MinIO

MinIO is a Kubernetes native application for cloud storage. Prior to version `RELEASE.2021-12-27T07-23-18Z`, a malicious client can hand-craft an HTTP API call that allows for updating policy for a user and gaining higher privileges. The patch in version `RELEASE.2021-12-27T07-23-18Z` changes the accepted request body type and removes the ability to apply policy changes through this API. There is a workaround for this vulnerability: Changing passwords can be disabled by adding an explicit `Deny` rule to disable the API for users.

Bypassing policy restrictions on regular users

Minio is a Kubernetes native application for cloud storage. All users on release `RELEASE.2021-10-10T16-53-30Z` are affected by a vulnerability that involves bypassing policy restrictions on regular users. Normally, checkKeyValid() should return owner true for rootCreds. In the affected version, policy restriction did not work properly for users who did not have service (svc) or security token service (STS) accounts. This issue is fixed in `RELEASE.2021-10-13T00-23-17Z`. A downgrade back to release `RELEASE.2021-10-08T23-58-24Z` is available as a workaround.

MITM modification of request bodies in MinIO

MinIO is an open-source high performance object storage service and it is API compatible with Amazon S3 cloud storage service. In MinIO before version RELEASE.2021-03-17T02-33-02Z, there is a vulnerability which enables MITM modification of request bodies that are meant to have integrity guaranteed by chunk signatures. In a PUT request using aws-chunked encoding, MinIO ordinarily verifies signatures at the end of a chunk. This check can be skipped if the client sends a false chunk size that is much greater than the actual data sent: the server accepts and completes the request without ever reaching the end of the chunk + thereby without ever checking the chunk signature. This is fixed in version RELEASE.2021-03-17T02-33-02Z. As a workaround one can avoid using "aws-chunked" encoding-based chunk signature upload requests instead use TLS. MinIO SDKs automatically disable chunked encoding signature when the server endpoint is configured with TLS.

Bypassing readOnly policy by creating a temporary 'mc share upload' URL

MinIO is an open-source high performance object storage service and it is API compatible with Amazon S3 cloud storage service. In MinIO before version RELEASE.2021-03-04T00-53-13Z it is possible to bypass a readOnly policy by creating a temporary 'mc share upload' URL. Everyone is impacted who uses MinIO multi-users. This is fixed in version RELEASE.2021-03-04T00-53-13Z. As a workaround, one can disable uploads with `Content-Type: multipart/form-data` as mentioned in the S3 API RESTObjectPOST docs by using a proxy in front of MinIO.

Server-Side Request Forgery in MinIO Browser API

MinIO is a High Performance Object Storage released under Apache License v2.0. In MinIO before version RELEASE.2021-01-30T00-20-58Z there is a server-side request forgery vulnerability. The target application may have functionality for importing data from a URL, publishing data to a URL, or otherwise reading data from a URL that can be tampered with. The attacker modifies the calls to this functionality by supplying a completely different URL or by manipulating how URLs are built (path traversal etc.). In a Server-Side Request Forgery (SSRF) attack, the attacker can abuse functionality on the server to read or update internal resources. The attacker can supply or modify a URL which the code running on the server will read or submit data, and by carefully selecting the URLs, the attacker may be able to read server configuration such as AWS metadata, connect to internal services like HTTP enabled databases, or perform post requests towards internal services which are not intended to be exposed. This is fixed in version RELEASE.2021-01-30T00-20-58Z, all users are advised to upgrade. As a workaround you can disable the browser front-end with "MINIO_BROWSER=off" environment variable.

Authentication bypass MinIO Admin API

MinIO versions before RELEASE.2020-04-23T00-58-49Z have an authentication bypass issue in the MinIO admin API. Given an admin access key, it is possible to perform admin API operations i.e. creating new service accounts for existing access keys - without knowing the admin secret key. This has been fixed and released in version RELEASE.2020-04-23T00-58-49Z.

Minio Inc. Minio S3 server version prior to RELEASE.2018-05-16T23-35-33Z contains a Allocation of Memory Without Limits or Throttling (similar to CWE-774) vulnerability in write-to-RAM that can result in Denial of Service. This attack appear to be exploitable via Sending V4-(pre)signed requests with large bodies . This vulnerability appears to have been fixed in after commit 9c8b7306f55f2c8c0a5c7cea9a8db9d34be8faa7.