CVE-2006-6717 in At-9000 24 Ethernetswitch
Summary
by MITRE
The Allied Telesis AT-9000/24 Ethernet switch accepts management packets from arbitrary VLANs, contrary to the documentation, which allows remote attackers to conduct attacks against the switch from unexpected locations.
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Analysis
by VulDB Data Team • 10/03/2017
The Allied Telesis AT-9000/24 Ethernet switch presents a significant security vulnerability classified as CVE-2006-6717, where the device fails to properly enforce VLAN isolation for management traffic. This flaw fundamentally undermines the network security model by allowing unauthorized remote access to switch management functions from any VLAN, bypassing the intended security boundaries that should isolate management traffic within specific virtual LANs. The vulnerability directly contradicts standard network security documentation and best practices, creating an attack surface that extends far beyond the device's intended operational scope. This misconfiguration enables attackers to exploit management protocols and interfaces without proper authentication or authorization, potentially compromising the entire network infrastructure.
The technical implementation of this vulnerability stems from the switch's failure to validate VLAN membership for incoming management packets. When management traffic arrives at the switch, the device should verify that the packet originates from an authorized VLAN before processing any management commands or responses. However, the AT-9000/24 fails to perform this critical validation step, allowing management packets from any VLAN to be processed regardless of their source. This represents a classic failure in access control implementation and violates fundamental security principles outlined in the CWE taxonomy under CWE-284, which addresses improper access control mechanisms. The switch essentially operates with a permissive security model rather than the restrictive approach that should be enforced for network management interfaces.
The operational impact of this vulnerability extends beyond simple unauthorized access, creating multiple attack vectors that can be leveraged by malicious actors. Remote attackers can exploit this weakness to perform administrative functions such as configuration changes, firmware updates, port status modifications, and access control policy alterations. This vulnerability enables attackers to potentially gain persistent access to the network infrastructure, create backdoors, or establish unauthorized network segments. The implications are particularly severe in enterprise environments where switch management interfaces often serve as critical entry points for network administrators and where unauthorized access could lead to complete network compromise. The vulnerability also aligns with ATT&CK framework technique T1046, which covers network service scanning, and T1059, which addresses command and scripting interpreters, as attackers can leverage the management interface to execute commands and establish persistence.
Mitigation strategies for CVE-2006-6717 should focus on implementing proper VLAN isolation controls and restricting management access to authorized networks only. Network administrators should configure the switch to enforce strict VLAN membership validation for all management traffic, ensuring that only packets originating from designated management VLANs are processed. This can be achieved through proper network segmentation, implementing access control lists, and configuring VLAN restrictions on management interfaces. The recommended approach includes disabling management access from untrusted VLANs, implementing network access control policies, and ensuring that management protocols such as SNMP, SSH, and HTTP/HTTPS are properly secured. Additionally, regular security audits should verify that management interfaces are not accessible from unauthorized network segments, and network monitoring should be implemented to detect anomalous management traffic patterns. Organizations should also consider implementing network segmentation strategies that separate management traffic from user traffic, following the principle of least privilege as outlined in NIST SP 800-53 security controls.