SeaweedFS up to 4.39 ACL allowed/protected.txt PutObjectAcl privileges management

Summaryinfo

A vulnerability identified as problematic has been detected in SeaweedFS up to 4.39. Impacted is the function PutObjectAcl of the file allowed/protected.txt of the component ACL Handler. Performing a manipulation results in privileges management. This vulnerability is reported as CVE-2026-77611. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as problematic has been found in SeaweedFS up to 4.39. This affects the function PutObjectAcl of the file allowed/protected.txt of the component ACL Handler. The manipulation with an unknown input leads to a privileges management vulnerability. CWE is classifying the issue as CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. This is going to have an impact on integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-77611 since 08/20/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

By approaching the search of inurl:allowed/protected.txt it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 4.40 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

• SeaweedFS

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28
• 4.29
• 4.30
• 4.31
• 4.32
• 4.33
• 4.34
• 4.35
• 4.36
• 4.37
• 4.38
• 4.39

Website

• Product: https://github.com/seaweedfs/seaweedfs/

CPE 2.3info

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