CVE-2026-42600: MinIO: Path Traversal via msgpack Body in `ReadMultiple` Storage-REST Endpoint

Vulnerability summary

CVE-2026-42600 is a medium (CVSS 6.9) Path Traversal vulnerability in minio. EPSS estimates a 0.47% chance of exploitation in the next 30 days, higher than 40% of scored vulnerabilities.

Timeline

1. 11-05-2026
   PublishedVulnerability first disclosed.
2. 15-05-2026
   Last modifiedVulnerability information updated.

Description

MinIO is a high-performance object storage system. From RELEASE.2022-07-24T01-54-52Z to before RELEASE.2026-04-14T21-32-45Z, 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. 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. This vulnerability is fixed in RELEASE.2026-04-14T21-32-45Z.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.