CVE-2004-2545 in Sidewinder G2
Summary
by MITRE
Secure Computing Corporation Sidewinder G2 6.1.0.01 allows remote attackers to cause a denial of service (SMTP proxy failure) via unknown attack vendors involving an "extremely busy network." NOTE: this might not be a vulnerability because the embedded monitoring sub-system automatically restarts after the failure.
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Analysis
by VulDB Data Team • 07/19/2017
The vulnerability described in CVE-2004-2545 affects the Secure Computing Corporation Sidewinder G2 6.1.0.01 firewall appliance, specifically within its SMTP proxy functionality. This device operates as a network security gateway that filters and monitors email traffic, implementing content filtering and security policies for enterprise email systems. The vulnerability manifests as a denial of service condition that occurs when the SMTP proxy component fails during periods of high network activity, creating a scenario where legitimate email traffic is disrupted and potentially blocked.
The technical flaw involves the SMTP proxy subsystem's inability to handle extremely high volumes of network traffic or concurrent connections, leading to a failure state that prevents the system from processing email messages. This represents a classic resource exhaustion or system stability issue where the proxy component becomes overwhelmed by network load, causing it to crash or become unresponsive. The vulnerability is categorized under CWE-400, which addresses "Uncontrolled Resource Consumption" or "Resource Exhaustion" conditions that can lead to denial of service attacks. The specific nature of the attack vector involves overwhelming the system with traffic from multiple vendors or sources simultaneously, creating a scenario where the embedded monitoring subsystem cannot maintain stable operation.
The operational impact of this vulnerability extends beyond simple service disruption, as it affects email communication flow within enterprise networks that rely on the Sidewinder G2 for security filtering. When the SMTP proxy fails, legitimate email traffic may be blocked or delayed, potentially causing business disruption and communication failures. Organizations using this appliance may experience cascading effects where email-based business processes are interrupted, affecting productivity and customer service. The vulnerability particularly impacts environments with high email volumes or those experiencing network congestion, making it more likely to occur during peak business hours or during periods of increased network activity.
While the vendor has noted that the embedded monitoring subsystem automatically restarts after failure, this remediation approach presents its own operational challenges. The automatic restart mechanism may introduce temporary service interruptions that could be unacceptable for mission-critical email systems, and the frequency of such restarts could indicate underlying stability issues that require deeper investigation. Organizations should consider implementing additional monitoring and alerting systems to track the frequency of these failures, as they may indicate that the appliance is operating beyond its designed capacity or that additional capacity planning is required. This situation aligns with ATT&CK technique T1499.004, which involves "Utilities: Endpoint Denial of Service" where adversaries may exploit system instability to cause service disruptions. The vulnerability demonstrates how seemingly benign network conditions can trigger system instability, highlighting the importance of capacity planning and robust system design in enterprise security appliances. Organizations should also consider implementing redundant email processing systems or load balancing strategies to minimize the impact of such failures on business operations.