CVE-2025-10230: 
Samba vulnerability analysis and mitigation

CVE-2025-10230 is a critical command injection vulnerability discovered in Samba's WINS server implementation. The vulnerability affects all Samba versions since 4.0 when configured as an Active Directory Domain Controller with WINS support enabled and a 'wins hook' parameter set. The flaw was discovered by Igor Morgenstern of Aisle Research and was publicly disclosed on October 15, 2025 (Samba Security, Security Online).

The vulnerability stems from insufficient input validation in the WINS server component of Samba Active Directory Domain Controllers. When the WINS server processes name changes, it executes the program specified by the 'wins hook' parameter without properly validating the input names. These names are directly inserted into shell commands, allowing attackers to inject shell metacharacters within the 15-character NetBIOS name limit. The vulnerability has received a CVSS v3.1 score of 10.0 (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H), indicating the highest possible severity (Samba Security).

The vulnerability enables unauthenticated remote code execution on affected Samba Active Directory Domain Controllers. An attacker can execute arbitrary commands on the host system without requiring any authentication, potentially leading to complete system compromise. It's worth noting that the vulnerability only affects domain controllers with WINS support enabled and a configured 'wins hook' parameter (Security Online).

Several mitigation options are available: 1) Upgrade to Samba versions 4.23.2, 4.22.5, or 4.21.9 which contain the security fix, 2) Avoid setting the 'wins hook' parameter in the smb.conf of a Samba AD Domain Controller, or 3) Ensure 'wins support' is set to 'no' (which is the default value). The Samba team has noted that the 'wins hook' parameter is unlikely to be useful on a domain controller and may not be supported in future releases (Samba Security).

The vulnerability has received significant attention due to its critical severity rating. The Ubuntu security team has classified it as a medium priority issue, noting that per Samba developers, this is an unusual configuration that "will affect very few, possibly zero, users" (Ubuntu Security).