Description

A critical vulnerability identified as CVE-2025-10230 has been discovered in Samba’s WINS server hook functionality, posing a major threat to systems running as Active Directory (AD) Domain Controllers. This flaw allows remote, unauthenticated attackers to execute arbitrary code simply by sending a specially crafted NetBIOS name to the vulnerable system. With a CVSSv3.1 score of 10.0, this issue impacts all Samba versions from 4.0 onward that have both WINS support and the wins hook parameter enabled in the configuration file (smb.conf). The vulnerability can be exploited without credentials or user interaction, making it a serious risk for complete system compromise, including data breaches, ransomware attacks, or infrastructure control. The root cause of the issue lies in how the Samba WINS server processes NetBIOS names. When the wins hook parameter is active, changes to WINS names trigger a shell command execution without properly sanitizing input. This allows attackers to inject malicious shell commands through specially crafted names, which then run with system-level privileges. Although WINS support is disabled by default, many organizations enable it for compatibility with older systems, inadvertently exposing their networks to this critical flaw. To mitigate the risk, administrators are strongly urged to upgrade to patched versions like Samba 4.23.2, 4.22.5, or 4.21.9 or apply the official patch from the Samba security portal. If immediate updates are not possible, disabling the wins hook setting or turning off WINS support entirely are effective interim solutions. Additionally, configurations should be audited to eliminate unnecessary hooks. Long-term, organizations should phase out legacy dependencies to avoid future exposure.