VULNERABILITY INTELLIGENCE

CVE-2023-4091

CVSS score6.5 MEDIUM
EPSS probability1.33%
CISA KEVNot currently listed
Published2023-11-03
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Description

A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured with "acl_xattr:ignore system acls = yes". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.

Weakness classification

  • CWE-276: Incorrect Default Permissions

Primary references