CVE-2026-109411 (GCVE-0-2026-109411)

Vulnerability from cvelistv5 – Published: 2026-10-28 19:17 – Updated: 2026-10-28 19:17
VLAI
Title
Samba: access control bypass via vfs_ceph_rgw case-insensitive open
Summary
An access control bypass flaw was found in Samba's vfs_ceph_rgw module in it's openat() function. An authenticated user can bypass access controls to read or overwrite restricted files on shares configured with the experimental vfs_ceph_rgw module. When a client requests an existing file using mismatched character casing, the module fails to perform a case-insensitive lookup correctly, causing the server to treat the operation as creating a new file. As a result, the server skips standard permission checks on the existing file, allowing the attacker to access or overwrite sensitive data owned by other users.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1062 records in the last 180 days details
References
Impacted products
Date Public
2026-10-23 15:00
Credits
Red Hat would like to thank hataehoon for reporting this issue.
Show details on NVD website
To clipboard 

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}



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