CVE-2026-77317CWE-863broken-access-control

CVE-2026-77317

High · published August 27, 2026

CVSS v3.1
8.1
EPSS
0%
Percentile
29.0
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.1 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00363 · 29.0th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-08-27T02:16Z
References (3)
EPSS history
Timeline
  • 28 AUG 06:53Z
    EPSS moved — → 0%
    epss
  • 26 AUG 21:25Z
    SeaweedFS: SFTP path ACL literal prefix match permits cross-tenant file read and overwrite
    cvelistv5