CVE-2023-4091

medium

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.

References

https://www.samba.org/samba/security/CVE-2023-4091.html

https://bugzilla.samba.org/show_bug.cgi?id=15439

https://bugzilla.redhat.com/show_bug.cgi?id=2241882

https://access.redhat.com/security/cve/CVE-2023-4091

https://access.redhat.com/errata/RHSA-2023:7467

https://access.redhat.com/errata/RHSA-2023:7464

https://access.redhat.com/errata/RHSA-2023:7408

https://access.redhat.com/errata/RHSA-2023:7371

https://access.redhat.com/errata/RHSA-2023:6744

https://access.redhat.com/errata/RHSA-2023:6209

Details

Source: Mitre, NVD

Published: 2023-11-03

Updated: 2024-09-16

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:C/A:N

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Severity: Medium