CVE-2001-0486 in BorderManager
Summary
by MITRE
Remote attackers can cause a denial of service in Novell BorderManager 3.6 and earlier by sending TCP SYN flood to port 353.
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Analysis
by VulDB Data Team • 12/25/2024
The vulnerability identified as CVE-2001-0486 represents a critical denial of service weakness in Novell BorderManager 3.6 and earlier versions that enables remote attackers to disrupt network services through a well-known attack pattern. This flaw specifically targets the BorderManager's handling of TCP SYN flood attacks directed at port 353, which serves as the default port for the BorderManager's administrative interface. The vulnerability stems from insufficient protection mechanisms within the BorderManager's TCP stack implementation, allowing malicious actors to exploit the system's inability to properly manage connection requests during high-volume SYN traffic patterns.
The technical nature of this vulnerability aligns with CWE-400, which addresses unchecked resource consumption, and specifically demonstrates how improper handling of network connection requests can lead to system exhaustion. When attackers flood port 353 with TCP SYN packets, the BorderManager system becomes overwhelmed with pending connection requests that are never properly completed, causing legitimate users to be unable to establish connections to the administrative interface. This represents a classic resource exhaustion attack pattern where the system's connection tracking mechanisms are bypassed or overwhelmed, leading to the service becoming unresponsive or completely unavailable.
The operational impact of this vulnerability extends beyond simple service disruption, as it affects the core administrative functionality of the BorderManager appliance. Network administrators rely on port 353 for critical management tasks including configuration changes, monitoring, and system maintenance. When this port becomes unavailable due to the SYN flood attack, it effectively removes the ability to manage the security appliance, creating a situation where the system becomes essentially unusable for its intended security purposes. This creates a dangerous scenario where network security is compromised not only through the denial of service but also through the inability to respond to or manage other security threats.
The attack vector for this vulnerability is particularly concerning as it requires minimal sophistication to execute successfully, making it accessible to a broad range of threat actors. The attack operates within the standard TCP three-way handshake process, leveraging the inherent weaknesses in how BorderManager handles incomplete connection sequences. This vulnerability can be exploited through various methods including automated tools that generate high-volume SYN traffic, potentially causing cascading effects that impact the entire network infrastructure relying on the BorderManager appliance for security services. Organizations using affected versions should consider implementing network-level protections such as SYN cookies or rate limiting, though these measures may not be sufficient against determined attackers with significant resources.
Mitigation strategies for CVE-2001-0486 should include immediate patching of affected BorderManager versions, as well as implementing network segmentation to isolate the administrative interface from general network traffic. The ATT&CK framework categorizes this type of attack under T1499, which covers network denial of service, and organizations should consider implementing intrusion detection systems that can identify and alert on unusual SYN traffic patterns. Additionally, the vulnerability highlights the importance of proper system hardening and the implementation of defense-in-depth strategies that include multiple layers of protection beyond simple access controls. Organizations should also establish incident response procedures specifically addressing denial of service attacks against critical infrastructure components to ensure rapid response and recovery capabilities when such vulnerabilities are exploited.