cve/2023/CVE-2023-4091.md

### [CVE-2023-4091](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-4091)
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![](https://img.shields.io/static/v1?label=Product&message=Red%20Hat%20Virtualization%204%20for%20Red%20Hat%20Enterprise%20Linux%208&color=blue)
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### 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.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/fkie-cad/nvd-json-data-feeds