cvedb.io
CVE-2026-42882
CRITICAL · CVSS 9.4
EPSS exploitation probability: 0%
Published 2026-05-11T20:25:44.450 · Last modified 2026-06-17T10:48:33.607

Summary

oxyno-zeta/s3-proxy is an aws s3 proxy written in go. Prior to 5.0.0, s3-proxy contains an authentication bypass caused by inconsistent URL path interpretation between the authentication middleware and the bucket handler. The authentication middleware evaluates resource path patterns against the percent-encoded request URI (r.URL.RequestURI()), while the bucket handler constructs S3 object keys from the decoded path (r.URL.Path). This mismatch, combined with the glob library being invoked without a path separator (causing * to match across / boundaries), allows unauthenticated attackers to write to, read from, or delete objects in protected S3 namespaces. Exploitation is possible via three techniques: (1) using * patterns that match across path separators to reach protected routes via path

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.