# CVE-2023-28433: Minio Privilege Escalation on Windows via Path separator manipulation

> Low-privilege users on Windows can escalate to admin by manipulating path separators to place objects in unauthorized buckets.

- **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:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Mar 2023
- **Updated:** 25 Feb 2025
- **Also known as:** GHSA-w23q-4hw3-2pp6, MINI-8x9f-qgw6-8mgp, MINI-pvfw-mwj4-mq3q

## What is CVE-2023-28433?

CVE-2023-28433 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. 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.

Weakness: CWE-668 (Exposure of Resource to Wrong Sphere)

## Which versions are affected by CVE-2023-28433?

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 | 0.0.0-202303200735 |
| `github.com/minio/minio` | Go | All versions | 0.0.0-202303200735 |

Products: Minio Minio.

## How do I fix CVE-2023-28433?

Upgrade github.com/minio/minio to 0.0.0-202303200735 or later.

## Is CVE-2023-28433 being exploited?

There is no known exploitation of CVE-2023-28433 in the wild and no public exploit code.

## Other vulnerabilities in minio

- [CVE-2023-28434](https://insights.sbomify.com/CVE-2023-28434/): MinIO Security Feature Bypass (high 8.8, exploited in the wild)
- [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)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-28433 and fix it if it is affected.

What it is: CVE-2023-28433 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: There is no known exploitation of CVE-2023-28433 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/minio/minio (Go): affected all versions; fixed in 0.0.0-202303200735
- github.com/minio/minio (Go): affected all versions; fixed in 0.0.0-202303200735

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-2023-28433/ (Markdown: https://insights.sbomify.com/CVE-2023-28433/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-28433
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-28433
- OSV: https://osv.dev/vulnerability/CVE-2023-28433

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-28433/
Summaries are generated and may contain mistakes; the official description above is the record.