CVE-2014-0239: The internal DNS server in Samba 4.x before 4.0.18 does not check the QR field in the header section of an...

Security readout for executives and security teams

This flaw can make Samba's built-in DNS server waste CPU and network bandwidth when it receives a specially forged DNS response. The business impact is service disruption, especially for environments relying on Samba for domain services and DNS. The source bundle does not show data theft, remote code execution, or confirmed active exploitation. Exposure is most likely where Samba 4.x before 4.0.18 uses the internal DNS server and accepts DNS traffic from untrusted or broad network sources. The bundle lists generic affected data as unavailable, so confirm against installed Samba versions and vendor package advisories. Prioritize remediation for Samba DNS servers supporting authentication or core network operations. Treat internet-facing or broadly reachable DNS deployments as higher urgency. For isolated legacy systems, schedule patching through normal maintenance after confirming exposure. Mitigation focus: Upgrade affected Samba 4.x deployments to 4.0.18 or later where applicable.; Apply distribution vendor Samba security updates, including relevant Gentoo guidance where used.; Restrict Samba DNS access to trusted networks and required clients only..

Prepared

Jun 14, 2026, 14:16 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.