Vulnerability Description
SeaweedFS is a distributed storage system for files and blobs. In versions prior to 4.40, an authenticated S3 principal with permissions scoped to a nested object key can overwrite a different object outside that scope by calling PutObjectAcl on the key it is allowed to access. The handler authorizes the request against the requested nested key but then writes the updated entry back to the bucket root rather than the key's actual parent directory, so an ACL change on allowed/protected.txt is instead applied to protected.txt at the bucket root. Because the update carries the full entry rather than only ACL metadata, an existing target object is overwritten with the content, metadata, owner information, and ACL of the scoped object, bypassing the object-level action scoping configured through the static S3 identity file. This issue is fixed in version 4.40.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/seaweedfs/seaweedfs/commit/311bc3a6dfbd042751692bc3de8accc516
- https://github.com/seaweedfs/seaweedfs/security/advisories/GHSA-9x53-cjpr-m682
- https://github.com/seaweedfs/seaweedfs/security/advisories/GHSA-9x53-cjpr-m682
FAQ
What is CVE-2026-77611?
CVE-2026-77611 is a vulnerability with a CVSS score of 7.1 (HIGH). SeaweedFS is a distributed storage system for files and blobs. In versions prior to 4.40, an authenticated S3 principal with permissions scoped to a nested object key can overwrite a different object ...
How severe is CVE-2026-77611?
CVE-2026-77611 has been rated HIGH with a CVSS base score of 7.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-77611?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.