#VU81872 Permissions, Privileges, and Access Controls in Samba - CVE-2023-4091
Vulnerability identifier: #VU81872
Vulnerability risk: Low
CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]
CVE-ID: CVE-2023-4091
CWE-ID:
CWE-264
Exploitation vector: Network
Exploit availability: No
Vulnerable software:
Samba
Server applications /
Directory software, identity management
Vendor: Samba
Description
The vulnerability allows a remote user to truncate read-only files.
The vulnerability exists due to an error in the way SMB protocol implementation in Samba handles file operations. A remote user can request read-only access to files and then truncate them to 0 bytes by opening files with OVERWRITE disposition when using the acl_xattr Samba VFS module with the smb.conf setting "acl_xattr:ignore system acls = yes".
Mitigation
Install updates from vendor's website.
Vulnerable software versions
Samba: 1.9.16 - 1.9.18, 2.0 - 2.0.10, 2.2a - 2.2.12, 2.18.3, 3.0 - 3.0.37, 3.1 - 3.1.0, 3.2 - 3.2.15, 3.3 - 3.3.16, 3.4 - 3.4.17, 3.5 - 3.5.22, 3.6.0 - 3.6.25, 4.0.0 - 4.0.26, 4.1.0 - 4.19.0, 4.2.0 - 4.2.14, 4.3.0 - 4.3.13, 4.4.0 rc4 - 4.4.16, 4.5.0 - 4.5.16, 4.6.0 - 4.6.16, 4.7.0 - 4.7.12, 4.8.0 - 4.8.12, 4.9.0 - 4.9.18
External links
https://www.samba.org/samba/security/CVE-2023-4091.html
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
