CVE-2002-1203 in Secureway Firewall
Summary
by MITRE
IBM SecureWay Firewall before 4.2.2 performs extra processing before determining that a packet is invalid and dropping it, which allows remote attackers to cause a denial of service (resource exhaustion) via a flood of malformed TCP packets without any flags set.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 10/27/2024
The vulnerability described in CVE-2002-1203 affects IBM SecureWay Firewall versions prior to 4.2.2, representing a significant security flaw that impacts network infrastructure devices. This issue stems from the firewall's inefficient packet processing logic where the system performs additional computational operations before recognizing that incoming packets are invalid and should be discarded. The flaw specifically targets TCP packets that lack any flags, which are typically considered malformed or suspicious in network communications. This design weakness creates a critical operational vulnerability that can be exploited by malicious actors to disrupt network services.
The technical implementation of this vulnerability involves the firewall's packet validation mechanism operating with suboptimal efficiency. When malformed TCP packets without any flags arrive at the firewall, the system's processing pipeline executes unnecessary operations before ultimately determining that these packets should be dropped. This extra processing consumes system resources including CPU cycles, memory allocation, and network bandwidth. The vulnerability falls under the category of resource exhaustion attacks where attackers can flood the firewall with these specially crafted malformed packets, causing the device to consume excessive computational resources and potentially leading to complete service disruption.
The operational impact of this vulnerability extends beyond simple denial of service, as it can severely compromise network availability and performance for legitimate users. When an attacker successfully exploits this flaw, the firewall becomes overwhelmed with processing tasks for invalid packets, creating a cascading effect that can degrade or completely halt network services. Network administrators may observe increased system load, reduced throughput, and potential complete service outages as the firewall struggles to handle the resource-intensive processing of malformed packets. This vulnerability particularly affects enterprise networks that rely on IBM SecureWay Firewalls for security perimeter protection, as these devices become vulnerable to simple but effective DoS attacks.
The attack pattern for exploiting this vulnerability aligns with common network reconnaissance and exploitation techniques documented in various threat frameworks. Attackers can easily construct and send large volumes of malformed TCP packets without flags to trigger the inefficient processing behavior, making this attack relatively simple to execute while maintaining significant impact. The vulnerability demonstrates poor defensive programming practices and highlights the importance of efficient input validation in security-critical systems. From an ATT&CK framework perspective, this vulnerability maps to techniques involving resource exhaustion and denial of service, specifically targeting network infrastructure components. Organizations should implement proper packet filtering rules to drop malformed packets at the earliest possible stage of network processing, and regularly update firewall firmware to address known vulnerabilities. The recommended mitigation strategy includes applying IBM's security patches for SecureWay Firewall version 4.2.2 and implementing network monitoring to detect unusual packet processing patterns that may indicate exploitation attempts. This vulnerability also underscores the need for robust software testing and validation processes, particularly for security devices where processing efficiency directly impacts system reliability and availability. The flaw represents a classic example of how inefficient code implementation can create significant security risks, emphasizing the importance of following secure coding practices and conducting thorough security assessments of network infrastructure components.