CVE-2001-0163 in Aironet
Summary
by MITRE
Cisco AP340 base station produces predictable TCP Initial Sequence Numbers (ISNs), which allows remote attackers to spoof or hijack TCP connections.
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Analysis
by VulDB Data Team • 11/24/2024
The vulnerability identified as CVE-2001-0163 affects Cisco AP340 base station devices and represents a critical weakness in the implementation of TCP connection security protocols. This issue stems from the predictable nature of Initial Sequence Numbers generated by the device's TCP stack, creating a significant security risk that enables malicious actors to exploit network communications. The vulnerability falls under the broader category of weak random number generation within network infrastructure components, making it particularly dangerous for wireless access point implementations that rely heavily on TCP for management and data transmission functions.
The technical flaw manifests in the deterministic generation of TCP Initial Sequence Numbers, which violates fundamental security principles required for secure network communications. When a TCP connection is established, each side generates an initial sequence number that should be unpredictable to prevent connection hijacking attempts. However, the Cisco AP340 implementation uses a predictable algorithm or insufficient entropy source for generating these numbers, allowing remote attackers to calculate or guess future sequence numbers. This weakness directly maps to CWE-330, which addresses the use of insufficiently random values, and represents a classic example of poor entropy implementation in cryptographic contexts. The predictable ISN generation creates a pathway for attackers to perform TCP session hijacking by accurately predicting sequence numbers and injecting malicious packets into established connections.
The operational impact of this vulnerability extends beyond simple network disruption to encompass full compromise of wireless network management and data transmission capabilities. Attackers can exploit this weakness to perform man-in-the-middle attacks, intercept sensitive communications, and potentially gain unauthorized access to network management interfaces. The vulnerability is particularly concerning for wireless infrastructure as it affects the fundamental security model of TCP connections that wireless access points depend upon for reliable operation. Network administrators may experience unauthorized access to wireless network configurations, data exfiltration, and potential denial of service conditions that can severely impact business continuity and security posture. This weakness is categorized under ATT&CK technique T1046, which involves network service scanning and exploitation of predictable network protocols.
Mitigation strategies for CVE-2001-0163 require immediate attention from network administrators and security teams responsible for wireless infrastructure management. The primary recommendation involves implementing network segmentation and access control measures to limit the attack surface and reduce the impact of potential exploitation. Network administrators should consider deploying TCP sequence number randomization techniques and ensuring that all network devices implement proper entropy sources for sequence number generation. The vulnerability also highlights the importance of regular security assessments and vulnerability scanning of network infrastructure components, as it demonstrates how legacy network equipment can harbor critical security flaws that persist for extended periods. Additionally, implementing network monitoring solutions that can detect anomalous TCP connection patterns and sequence number predictions can provide early warning capabilities for potential exploitation attempts. Organizations should also consider upgrading affected hardware to versions that address the predictable sequence number generation issue, as this represents a fundamental flaw in the device's security architecture that cannot be effectively mitigated through software patches alone.