CVE-2007-0548 in HTTP Server
Summary
by MITRE
KarjaSoft Sami HTTP Server 2.0.1 allows remote attackers to cause a denial of service (daemon hang) via a large number of requests for nonexistent objects.
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Analysis
by VulDB Data Team • 08/19/2024
The KarjaSoft Sami HTTP Server version 2.0.1 contains a critical vulnerability that enables remote attackers to execute denial of service attacks through excessive requests for non-existent resources. This vulnerability represents a classic resource exhaustion flaw that can bring the entire web service to a halt, effectively preventing legitimate users from accessing the server's content. The vulnerability specifically manifests when the server receives a large volume of requests targeting objects that do not exist within the server's file system or application framework. The server's processing mechanism fails to properly handle these malformed or excessive request patterns, leading to daemon hanging conditions that require manual intervention or system restarts to resolve.
The technical implementation of this vulnerability stems from inadequate input validation and request handling within the server's core processing loop. When multiple concurrent requests are made for non-existent objects, the server's internal state management becomes overwhelmed, causing it to enter a non-responsive state where it stops processing legitimate requests while continuing to consume system resources. This behavior aligns with CWE-400, which classifies the vulnerability as an Uncontrolled Resource Consumption issue, where the server fails to properly manage its resource allocation in response to abnormal request patterns. The flaw demonstrates poor error handling practices where the server does not implement appropriate rate limiting or request queuing mechanisms to prevent resource exhaustion scenarios.
From an operational perspective, this vulnerability presents a significant risk to organizations relying on the KarjaSoft Sami HTTP Server for web services. Attackers can easily exploit this weakness using automated tools to flood the server with requests, causing service disruption that can last from minutes to hours depending on the server's configuration and available resources. The impact extends beyond simple service interruption as the daemon hang condition can potentially affect other services running on the same system, leading to cascading failures within the network infrastructure. This vulnerability particularly affects web applications that depend on continuous availability, such as e-commerce platforms, content management systems, or any service requiring consistent server response times.
Security practitioners should implement immediate mitigations including network-level rate limiting to restrict the number of requests per client within a given time window, which aligns with ATT&CK technique T1499.1 for resource exhaustion attacks. Additionally, implementing proper request validation and connection timeout mechanisms can prevent the server from becoming overwhelmed by excessive requests. Organizations should also consider deploying intrusion detection systems that can identify and alert on unusual request patterns that may indicate exploitation attempts. The vulnerability serves as a reminder of the importance of robust input validation and resource management in web server implementations, as outlined in industry best practices for secure coding standards. Regular security assessments and vulnerability scanning should be conducted to identify similar weaknesses in other server components, particularly those that may exhibit similar resource exhaustion behaviors when processing malformed inputs.