Exploited
high
8.8
CWE
269
Advisory Published
Advisory Published
Updated

CVE-2023-28434: MinIO Security Feature Bypass Vulnerability

First published: Wed Mar 22 2023(Updated: )

### Impact An attacker can use crafted requests to bypass metadata bucket name checking and put an object into any bucket while processing `PostPolicyBucket`. To carry out this attack, the attacker requires credentials with `arn:aws:s3:::*` permission, as well as enabled Console API access. ### Patches ``` commit 67f4ba154a27a1b06e48bfabda38355a010dfca5 Author: Aditya Manthramurthy <donatello@users.noreply.github.com> Date: Sun Mar 19 21:15:20 2023 -0700 fix: post policy request security bypass (#16849) ``` ### Workarounds Browser API access must be enabled turning off `MINIO_BROWSER=off` allows for this workaround. ### References The vulnerable code: ```go // minio/cmd/generic-handlers.go func setRequestValidityHandler(h http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { // ... // For all other requests reject access to reserved buckets bucketName, _ := request2BucketObjectName(r) if isMinioReservedBucket(bucketName) || isMinioMetaBucket(bucketName) { if !guessIsRPCReq(r) && !guessIsBrowserReq(r) && !guessIsHealthCheckReq(r) && !guessIsMetricsReq(r) && !isAdminReq(r) && !isKMSReq(r) { if ok { tc.FuncName = "handler.ValidRequest" tc.ResponseRecorder.LogErrBody = true } writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrAllAccessDisabled), r.URL) return } } // ... ```

Credit: security-advisories@github.com security-advisories@github.com security-advisories@github.com

Affected SoftwareAffected VersionHow to fix
MinIO MinIO<2023-03-20t20-16-18z
go/github.com/minio/minio<0.0.0-202303200415
0.0.0-202303200415

Remedy

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Remedy

https://github.com/minio/minio/commit/67f4ba154a27a1b06e48bfabda38355a010dfca5

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Reference Links

Frequently Asked Questions

  • What is the impact of CVE-2023-28434?

    An attacker can use crafted requests to bypass metadata bucket name checking and put an object into any bucket while processing `PostPolicyBucket`. To carry out this attack, the attacker requires credentials with `arn:aws:s3:::*` permission, as well as enabled Console API access.

  • How can an attacker exploit CVE-2023-28434?

    The attacker can use crafted requests and bypass metadata bucket name checking to put an object into any bucket.

  • What permissions do attackers need to exploit CVE-2023-28434?

    Attackers require credentials with `arn:aws:s3:::*` permission and enabled Console API access.

  • What is the severity of CVE-2023-28434?

    The severity of CVE-2023-28434 is high with a CVSS score of 8.8.

  • Where can I find more information about CVE-2023-28434?

    You can find more information about CVE-2023-28434 in the following references: [GitHub Advisory](https://github.com/minio/minio/security/advisories/GHSA-2pxw-r47w-4p8c), [NVD](https://nvd.nist.gov/vuln/detail/CVE-2023-28434), [GitHub Pull Request](https://github.com/minio/minio/pull/16849)

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