CVE-2000-0522 in ACE Server
Summary
by MITRE
RSA ACE/Server allows remote attackers to cause a denial of service by flooding the server s authentication request port with UDP packets, which causes the server to crash.
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Analysis
by VulDB Data Team • 04/05/2019
The RSA ACE/Server vulnerability identified as CVE-2000-0522 represents a critical denial of service weakness that exploits the server's handling of authentication requests through the User Datagram Protocol. This vulnerability specifically targets the authentication port, which serves as the primary communication channel for legitimate authentication transactions within the RSA ACE/Server framework. The flaw stems from insufficient input validation and resource management mechanisms within the server's UDP packet processing logic, creating an exploitable condition where malformed or excessive UDP traffic can trigger system instability.
The technical implementation of this vulnerability demonstrates a classic resource exhaustion attack pattern where malicious actors flood the designated authentication port with UDP packets to overwhelm the server's processing capabilities. When the server receives these flood packets, it fails to properly handle the malformed data streams, leading to memory corruption or process termination that ultimately results in complete service disruption. This issue falls under the CWE-400 category of Uncontrolled Resource Consumption, specifically manifesting as a denial of service through resource exhaustion. The vulnerability is particularly dangerous because it operates at the network protocol level, making it difficult to distinguish between legitimate authentication traffic and malicious attack traffic.
From an operational perspective, this vulnerability creates significant business impact for organizations relying on RSA ACE/Server for authentication services. The remote exploit capability means that attackers can initiate attacks from anywhere on the network without requiring local access or credentials, making the vulnerability extremely accessible. When successful, the attack causes complete service disruption that can affect thousands of users simultaneously, as the authentication server becomes unavailable for legitimate authentication requests. This disruption can cascade through dependent systems and applications that rely on successful authentication for access control, potentially leading to broader service outages. The attack requires minimal resources from the attacker and can be executed using simple network flooding tools, making it particularly dangerous in enterprise environments where authentication servers are critical infrastructure components.
Organizations should implement immediate network-level mitigations including firewall rules that limit UDP traffic to the authentication port to authorized sources only. The recommended approach involves deploying ingress filtering that restricts access to the authentication port based on source IP addresses and implementing rate limiting mechanisms to prevent UDP packet flooding. Network administrators should also configure intrusion detection systems to monitor for unusual traffic patterns on the authentication port and establish automated alerting for potential exploitation attempts. Additionally, organizations should consider implementing redundant authentication mechanisms and load balancing solutions to maintain service availability during potential attacks. The mitigation strategy should align with the ATT&CK framework's defensive techniques for network traffic filtering and access control, specifically targeting the T1071.004 technique related to application layer protocol usage and T1499.004 for network denial of service attacks. Regular security assessments and vulnerability scanning should be conducted to identify similar weaknesses in related network services and ensure comprehensive protection against similar exploitation patterns.