CVE-2012-0369 in 2100 Wireless LAN Controller
Summary
by MITRE
Cisco Wireless LAN Controller (WLC) devices with software 6.0 and 7.0 before 7.0.220.0, 7.1 before 7.1.91.0, and 7.2 before 7.2.103.0 allow remote attackers to cause a denial of service (device reload) via a sequence of IPv6 packets, aka Bug ID CSCtt07949.
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Analysis
by VulDB Data Team • 04/09/2017
The vulnerability described in CVE-2012-0369 represents a critical denial of service flaw affecting Cisco Wireless LAN Controller devices operating within specific software versions. This vulnerability specifically impacts WLC devices running software versions 6.0 and 7.0 before 7.0.220.0, 7.1 before 7.1.91.0, and 7.2 before 7.2.103.0, creating a significant operational risk for wireless network infrastructure. The flaw manifests through a carefully crafted sequence of IPv6 packets that, when processed by the affected devices, triggers an unexpected device reload mechanism. This vulnerability falls under the category of improper input validation as outlined in CWE-20, where the system fails to properly validate and handle incoming network traffic. The issue is particularly concerning because it allows remote attackers to exploit the vulnerability without requiring authentication or physical access to the network infrastructure.
The technical implementation of this vulnerability exploits weaknesses in the IPv6 packet processing logic within the WLC software stack. When the affected devices receive a sequence of specially crafted IPv6 packets, the processing routine fails to properly handle the packet structures, leading to a buffer overflow condition or memory corruption that ultimately results in an automatic device reload. This behavior represents a classic example of a resource exhaustion attack pattern where the attacker leverages legitimate network protocols to consume system resources in a way that causes the device to restart. The vulnerability is categorized under ATT&CK technique T1499.004 for Network Denial of Service and T1595.001 for Network Device Denial of Service, highlighting its potential for disrupting critical network infrastructure operations. The specific nature of the attack vector indicates that the vulnerability exists in the network protocol handling layer of the WLC software, where IPv6 packet validation and processing routines are insufficient to handle malformed or unexpected packet sequences.
The operational impact of this vulnerability extends far beyond simple service disruption, as WLC devices serve as critical components in enterprise wireless network infrastructure, managing authentication, encryption, and network access control for numerous wireless clients. When these devices experience unexpected reloads, they temporarily lose their ability to manage wireless network access, potentially affecting hundreds or thousands of users depending on the network size and configuration. The frequency and duration of these reload events can lead to significant business disruption, particularly in environments where wireless connectivity is essential for operations such as healthcare facilities, financial institutions, or manufacturing plants. Organizations may experience cascading effects where wireless outages impact other network-dependent systems, including security monitoring tools, inventory management systems, and communication platforms that rely on wireless connectivity for full functionality. The vulnerability also poses risks to network availability and reliability, as repeated exploitation attempts could cause sustained service degradation or complete network outages.
Mitigation strategies for this vulnerability should focus on immediate software patching and network-level protections. Organizations must prioritize upgrading their WLC devices to versions that contain the necessary security fixes, specifically targeting the software versions mentioned in the CVE description where patches are available. The Cisco security advisory for this vulnerability provides detailed information about the affected software versions and the recommended patching procedures. Network administrators should implement ingress filtering and packet filtering rules to restrict IPv6 traffic that could potentially trigger the vulnerability, although this approach may not be comprehensive given the nature of the attack. Additional protective measures include monitoring network traffic for unusual patterns of IPv6 packet sequences and implementing intrusion detection systems that can identify and alert on suspicious network behavior. Organizations should also consider network segmentation strategies to limit the potential impact of exploitation attempts and maintain detailed incident response procedures that account for wireless network infrastructure failures. The vulnerability underscores the importance of maintaining current security patches and following vendor security advisories to protect against known exploits that could compromise critical network infrastructure components.