CVE-2026-55874: SeaweedFS: Path traversal in the S3 gateway X-Amz-Copy-Source header allows cross-bucket object read

Published Jul 8, 2026
·
Updated

SeaweedFS is a distributed storage system. Prior to 4.34, the S3 API gateway does not reject dot-dot path segments in the X-Amz-Copy-Source header used by CopyObject and UploadPartCopy, allowing an authenticated identity scoped to one bucket to read objects from other buckets through server-side copy. This issue is fixed in version 4.34.

Affected Software

1 affected component
seaweedfs seaweedfs<4.34

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade SeaweedFS S3 API gateway to a version that resolves this vulnerability.

    Fixed in 4.34

Event History

Jul 8, 2026
CVE Published
via MITRE·02:43 PM
Data Sourced
via MITRE·02:43 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:16 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2026-55874?

The severity of CVE-2026-55874 is rated as high with a score of 7.7.

2

How do I fix CVE-2026-55874?

To fix CVE-2026-55874, upgrade to SeaweedFS version 4.34 or later, where the vulnerability has been addressed.

3

What does CVE-2026-55874 allow attackers to do?

CVE-2026-55874 allows attackers to perform path traversal via the X-Amz-Copy-Source header, enabling them to read objects from unauthorized buckets.

4

Which software is affected by CVE-2026-55874?

CVE-2026-55874 affects SeaweedFS versions prior to 4.34.

5

Is authentication required to exploit CVE-2026-55874?

Yes, CVE-2026-55874 requires that the attacker has an authenticated identity scoped to one bucket to exploit the vulnerability.

Contact

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