# CVE-2023-28434: MinIO Security Feature Bypass

> An attacker with specific permissions can bypass bucket checks to write objects to any bucket, requiring enabled Console API access.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 19 Sep 2023 (CISA KEV)
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Mar 2023
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-2pxw-r47w-4p8c, MINI-4h7r-f3w5-mrq6, MINI-f4gp-rm3q-w7ww

## What is CVE-2023-28434?

CVE-2023-28434 is a high-severity vulnerability in minio, published on 22 Mar 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Minio is a Multi-Cloud Object Storage framework. Prior to RELEASE.2023-03-20T20-16-18Z, 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. This issue has been patched in RELEASE.2023-03-20T20-16-18Z. As a workaround, enable browser API access and turn off `MINIO_BROWSER=off`.

Weakness: CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2023-28434?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/minio/minio` | Go | All versions | 0.0.0-202303200415 |
| `github.com/minio/minio` | Go | All versions | 0.0.0-202303200415 |

Products: Minio Minio.

## How do I fix CVE-2023-28434?

Upgrade github.com/minio/minio to 0.0.0-202303200415 or later. US federal agencies must fix it by 10 Oct 2023.

## Is CVE-2023-28434 being exploited?

Yes. Attackers have exploited CVE-2023-28434 in the wild since at least 19 Sep 2023.

Public exploit code:

- EXP for CVE-2023-28434 MinIO unauthorized to RCE (github_poc): https://github.com/AbelChe/evil_minio

## Other vulnerabilities in minio

- [CVE-2023-28432](https://insights.sbomify.com/CVE-2023-28432/): MinIO Information Disclosure (high 7.5, exploited in the wild)
- [CVE-2020-11012](https://insights.sbomify.com/CVE-2020-11012/): Authentication bypass MinIO Admin API (critical 9.3)
- [CVE-2026-33322](https://insights.sbomify.com/CVE-2026-33322/): MinIO: JWT Algorithm Confusion in OIDC Authentication (critical 9.2)
- [CVE-2026-33419](https://insights.sbomify.com/CVE-2026-33419/): MinIO: LDAP login brute-force via user enumeration and missing rate limit (critical 9.1)
- [CVE-2026-40344](https://insights.sbomify.com/CVE-2026-40344/): MinIO has an Unauthenticated Object Write via Missing Signature Verification in Unsigned-Trailer Uploads (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-28434 and fix it if it is affected.

What it is: CVE-2023-28434 is a high-severity vulnerability in minio, published on 22 Mar 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2023-28434 in the wild since at least 19 Sep 2023.

Affected packages and fixed versions:
- github.com/minio/minio (Go): affected all versions; fixed in 0.0.0-202303200415
- github.com/minio/minio (Go): affected all versions; fixed in 0.0.0-202303200415

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-28434/ (Markdown: https://insights.sbomify.com/CVE-2023-28434/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-28434
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-28434
- OSV: https://osv.dev/vulnerability/CVE-2023-28434

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-28434/
Summaries are generated and may contain mistakes; the official description above is the record.