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TI-2026-53965 Aliases CVE-2026-77317

SeaweedFS: SFTP path ACL literal prefix match permits cross-tenant file read and overwrite

Priority HIGH 70CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-863.

Summary

SeaweedFS is a distributed storage system for files and blobs. In versions from 3.88 through 4.39, the SFTP server evaluates configured path permissions with a literal string-prefix comparison, so a user scoped to a path is also granted the same access to any sibling path whose name merely begins with the same characters. A user granted access to /tenants/alice therefore also matches /tenants/alice-archive, /tenants/alice2, and similar siblings, because the check does not require a path-component boundary. An authenticated low-privilege SFTP user with a root home directory and narrow path permissions can thereby cross the configured ACL boundary to read another tenant's files, and to overwrite them if granted write, all through the documented SFTP service with its own valid credentials. This issue is fixed in version 4.40.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00363 30th percentileScored 2026-11-07
Fix Fixed seaweedfs (seaweedfs): 4.40

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
seaweedfsseaweedfs3.88 to before 4.404.40Patch availableCNA
  • seaweedfs Vendorseaweedfs Affected 3.88 to before 4.40 Fixed in 4.40 Patch available CNA

Remediation

  • Fix · CNA seaweedfs (seaweedfs) Fixed in 4.40

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-77317

References

Other 2

  • TI-2026-39686 SeaweedFS: Path traversal in the S3 and Iceberg REST gateways allows cross-bucket access CVSS 4.0HIGH 7.8
  • TI-2024-26879 seaweedfs v3.68 was discovered to contain a SQL injection vulnerability via the component… CVSS 3.1MEDIUM 6.5
  • TI-2026-42003 SeaweedFS < 4.34 - Cross-Bucket Object Deletion via DeleteObjects Request-Body Keys CVSS 4.0HIGH 7.2
  • TI-2026-74336 Hard-coded SSH host key in SeaweedFS SFTP Helm chart CVSS 4.0HIGH 7.0
  • TI-2026-54097 Incorrect authorization in seaweedfs CVSS 3.1HIGH 7.1
  • TI-2026-51136 SeaweedFS: Unauthenticated filer IAM gRPC service grants S3 administrative control CVSS 3.1CRITICAL 9.8
See all 13 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences