CVE-2007-4012 in Wireless LAN Controller
Summary
by MITRE
Cisco 4100 and 4400, Airespace 4000, and Catalyst 6500 and 3750 Wireless LAN Controller (WLC) software 4.1 before 4.1.180.0 allows remote attackers to cause a denial of service (ARP storm) via a broadcast ARP packet that "targets the IP address of a known client context", aka CSCsj50374.
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Analysis
by VulDB Data Team • 07/22/2019
The vulnerability identified as CVE-2007-4012 affects Cisco wireless LAN controller software versions 4.1 before 4.1.180.0 across multiple device families including Cisco 4100 and 4400 series, Airespace 4000, and Catalyst 6500 and 3750 wireless controllers. This issue represents a significant denial of service weakness that can be exploited remotely by malicious actors to disrupt network operations. The vulnerability specifically targets the handling of broadcast ARP packets within the wireless controller's network processing mechanisms, creating a condition where legitimate network traffic becomes overwhelmed by maliciously crafted packets.
The technical flaw manifests when a remote attacker sends a broadcast ARP packet that specifically targets the IP address of a known client context within the wireless controller's memory space. This particular packet construction triggers a flaw in the controller's ARP processing logic where the system enters an infinite loop or excessive processing state when encountering such malformed broadcast traffic. The vulnerability operates at the network layer, specifically exploiting the Address Resolution Protocol implementation within the wireless controller software, which is categorized under CWE-129 as improper validation of array indices and CWE-400 as unchecked resource consumption. The flaw essentially causes the wireless controller to continuously process the malicious ARP packet, leading to resource exhaustion and ultimately a complete denial of service condition.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise the entire wireless network infrastructure managed by the affected controllers. When exploited successfully, the ARP storm generated by the malicious packet causes the wireless controller to become unresponsive, preventing legitimate wireless clients from connecting to the network and disrupting all wireless services. Network administrators may experience complete loss of wireless connectivity for users within the affected coverage area, with the severity of impact directly correlating to the number of wireless clients connected to the compromised controller. This vulnerability particularly affects enterprise wireless networks where these controllers are commonly deployed, potentially impacting business operations, employee productivity, and critical wireless services that depend on stable network connectivity.
Mitigation strategies for CVE-2007-4012 should prioritize immediate software updates to version 4.1.180.0 or later, which contain patches specifically addressing the ARP processing flaw. Network administrators should implement network segmentation and access control measures to limit exposure, particularly by restricting direct internet access to wireless controllers and implementing proper firewall rules to filter malicious ARP traffic. The mitigation approach aligns with ATT&CK technique T1499.002 for network denial of service attacks, where adversaries leverage protocol weaknesses to exhaust system resources. Additional defensive measures include implementing network monitoring solutions that can detect unusual ARP traffic patterns and establishing incident response procedures to quickly identify and isolate affected controllers. Organizations should also consider deploying intrusion detection systems capable of identifying the specific packet signatures associated with this vulnerability to provide early warning capabilities and reduce the time between exploitation and response.