Answer in brief
CVE-2026-42600 records a Medium severity (CVSS 4.9) vulnerability in MinIO vulnerable to Path Traversal via msgpack Body in `ReadMultiple` Storage-REST Endpoint in github.com/minio/minio. The current sources do not mark it as known exploited. The current feed maps github.com/minio/minio (go), github.com/minio/minio (go), github.com/minio/minio (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 4.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps github.com/minio/minio (go), github.com/minio/minio (go), github.com/minio/minio (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| github.com/minio/miniogo | >=0 | Not reported |
| github.com/minio/miniogo | >=0.0.0-20220724015452,<0.0.0-20260414213245 | 0.0.0-20260414213245 |
| github.com/minio/miniogo | >=0.0.0-20220724015452 <0.0.0-20260414213245 | 0.0.0-20260414213245 |
Published upstream
May 5, 2026
Evidence: source:osv:source_dates:source-dates:recordSource modified
Oct 8, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Jun 11, 2026
### Impact _What kind of vulnerability is it? Who is impacted?_ A path traversal vulnerability in MinIO's `ReadMultiple` internode storage-REST endpoint allows a caller holding the cluster root JWT to read files from outside the configured drive roots, bounded only by the MinIO process UID. Distributed-erasure (multi-node) MinIO deployments are impacted. Single-node standalone deployments do not register the route and are not affected. The attack requires an HS512 JWT signed with `MINIO_ROOT_PASSWORD` and carrying `accessKey = MINIO_ROOT_USER` — the same secret every peer in the cluster holds to authenticate internode traffic, so a compromised peer or any actor in possession of the root credential can mint one. The `ReadMultiple` handler (`cmd/storage-rest-server.go`) decodes a msgpack `ReadMultipleReq` body containing `Bucket`, `Prefix`, and `Files` fields and forwards them to `xlStorage.ReadMultiple` (`cmd/xl-storage.go`) without validation: ```go volumeDir := pathJoin(s.drivePath, req.Bucket) // traversal resolves here for _, f := range req.Files { fullPath := pathJoin(volumeDir, req.Prefix, f) data, mt, err = s.readAllDataWithDMTime(ctx, req.Bucket, volumeDir, fullPath) } ``` `pathJoin` calls `path.Clean`, which resolves `..` components and produces an absolute path anywhere on the filesystem — it is not a root jail. The global `setRequestValidityMiddleware` rejects `..` in `r.URL.Path` and `r.Form` but does not inspect request bodies, so msgpack-encoded traversal bypasses it. Sibling storage methods (`StatInfoFile`, `ReadFileHandler`, `ReadVersion`) validate their volume argument through `s.getVolDir(volume)`, which rejects `..`; `ReadMultiple` skips this call. The attacker sends `POST /minio/storage/{drivePath}/v63/rmpl` with a msgpack-encoded body carrying `../` sequences in the `Bucket` field. The server opens the resulting path via `os.OpenFile` with `O_RDONLY|O_NOATIME` and returns its contents in the msgpack response stream. **Impact by deployment:** - **Bare-metal with `User=minio` in the systemd unit** — the `O_NOATIME` ownership check bounds the read to files owned by the MinIO UID. Reachable secrets include TLS private keys, KMS/KES key material, systemd credentials, and data belonging to other tenants sharing the same UID on the host. Secrets leaked this way persist across cluster credential rotation. - **Containerized running as UID 0** (the historical default for the official Docker image, `docker-compose` examples, and Helm charts without `securityContext.runAsNonRoot`) — the primitive escalates to arbitrary host-filesystem disclosure: `/etc/shadow`, `/root/**`, Kubernetes service-account tokens, cloud-init metadata caches. **Affected components:** `cmd/storage-rest-server.go` (`ReadMultiple` handler), `cmd/xl-storage.go` (`xlStorage.ReadMultiple`). **CWE:** CWE-22 (Improper Limitation of a Pathname to a Restricted Directory — 'Path Traversal') **CVSS v4.0 Score:** 6.9 (Medium) **Vector:** `CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N` ### Affected Versions All MinIO releases from `RELEASE.2022-07-24T01-54-52Z` through the final release of the minio/minio open-source project, `RELEASE.2025-09-07T16-13-09Z`. The vulnerability was introduced in commit [`f939d1c18`](https://github.com/minio/minio/commit/f939d1c1831c71f4b1c14df6d9cd62b12ccce7a3) ("Independent Multipart Uploads", [PR #15346](https://github.com/minio/minio/pull/15346)), which added the `ReadMultiple` storage-REST endpoint as part of the multipart upload redesign. The first affected release is `RELEASE.2022-07-24T01-54-52Z`. ### Patches **Fixed in**: MinIO AIStor `RELEASE.2026-04-14T21-32-45Z` (recommended upgrade target). The fix — which removed the `ReadMultiple` handler, the corresponding storage-driver method, the msgpack datatypes, the REST-client wrapper, and the route registration — first shipped in **MinIO AIStor `RELEASE.2024-10-23T19-38-07Z`**. Every AIStor release from `RELEASE.2024-10-23T19-38-07Z` onward is unaffected; users should upgrade to `RELEASE.2026-04-14T21-32-45Z` or later to pick up the accumulated fixes and improvements shipped since. #### Binary Downloads | Platform | Architecture | Download | | -------- | ------------ | --------------------------------------------------------------------------- | | Linux | amd64 | [minio](https://dl.min.io/aistor/minio/release/linux-amd64/minio) | | Linux | arm64 | [minio](https://dl.min.io/aistor/minio/release/linux-arm64/minio) | | macOS | arm64 | [minio](https://dl.min.io/aistor/minio/release/darwin-arm64/minio) | | macOS | amd64 | [minio](https://dl.min.io/aistor/minio/release/darwin-amd64/minio) | | Windows | amd64 | [minio.exe](https://dl.min.io/aistor/minio/release/windows-amd64/minio.exe) | #### FIPS Binaries | Platform | Architecture | Download | | -------- | ------------ | --------------------------------------------------------------------------- | | Linux | amd64 | [minio.fips](https://dl.min.io/aistor/minio/release/linux-amd64/minio.fips) | | Linux | arm64 | [minio.fips](https://dl.min.io/aistor/minio/release/linux-arm64/minio.fips) | #### Package Downloads | Format | Architecture | Download | | ------ | ------------ | ----------------------------------------------------------------------------------------------------------------------------------- | | DEB | amd64 | [minio_20260414213245.0.0_amd64.deb](https://dl.min.io/aistor/minio/release/linux-amd64/minio_20260414213245.0.0_amd64.deb) | | DEB | arm64 | [minio_20260414213245.0.0_arm64.deb](https://dl.min.io/aistor/minio/release/linux-arm64/minio_20260414213245.0.0_arm64.deb) | | RPM | amd64 | [minio-20260414213245.0.0-1.x86_64.rpm](https://dl.min.io/aistor/minio/release/linux-amd64/minio-20260414213245.0.0-1.x86_64.rpm) | | RPM | arm64 | [minio-20260414213245.0.0-1.aarch64.rpm](https://dl.min.io/aistor/minio/release/linux-arm64/minio-20260414213245.0.0-1.aarch64.rpm) | #### Container Images ```bash # Standard docker pull quay.io/minio/aistor/minio:RELEASE.2026-04-14T21-32-45Z podman pull quay.io/minio/aistor/minio:RELEASE.2026-04-14T21-32-45Z # FIPS docker pull quay.io/minio/aistor/minio:RELEASE.2026-04-14T21-32-45Z.fips podman pull quay.io/minio/aistor/minio:RELEASE.2026-04-14T21-32-45Z.fips ``` #### Homebrew (macOS) ```bash brew install minio/aistor/minio ``` ### Workarounds - [Users of the open-source `minio/minio` project should upgrade to MinIO AIStor `RELEASE.2026-04-14T21-32-45Z` or later.](https://docs.min.io/enterprise/aistor-object-store/upgrade-aistor-server/community-edition/) If upgrading is not immediately possible: - **Rotate the root credential and restrict who holds it.** The exploit requires a JWT signed with `MINIO_ROOT_PASSWORD`. Treat the root credential as the host-filesystem disclosure primitive that it is: rotate it after any suspected exposure, store it only in the secret manager that bootstraps the cluster, and do not hand it to applications or operators who only need object-level access. - **Do not run the MinIO container as UID 0.** Set `securityContext.runAsNonRoot: true` (and a non-zero `runAsUser`) in Kubernetes manifests, or add `--user` to `docker run`. This reduces the blast radius from arbitrary host-filesystem disclosure to MinIO-UID-owned files only. - **Restrict the internode storage-REST port at the network layer.** In distributed deployments, the storage-REST route is served on the same port as the S3 API by default. Where feasible, use `--internode-port` to expose internode traffic on a separate interface reachable only from other cluster peers, and block that interface from client networks. ### Credits - **Finders:** Discovered by Claude, Anthropic's AI assistant, and triaged by **Adrian Denkiewicz** at **Doyensec** in collaboration with **Anthropic Research**. ### Resources - Introducing commit: [`f939d1c18`](https://github.com/minio/minio/commit/f939d1c1831c71f4b1c14df6d9cd62b12ccce7a3) ([PR #15346](https://github.com/minio/minio/pull/15346)) - [CWE-22 — Improper Limitation of a Pathname to a Restricted Directory](https://cwe.mitre.org/data/definitions/22.html) - [CVE-2022-35919 — MinIO admin-authenticated path traversal in server-update endpoint (same class, different channel)](https://github.com/minio/minio/security/advisories/GHSA-gr9v-6pcm-rqvg) - [MinIO AIStor](https://min.io/aistor)
Quoted source text, attributed separately from HOL analysis.