CVE-2011-1785 in ESXi
Summary
by MITRE
VMware ESXi 4.0 and 4.1 and ESX 4.0 and 4.1 allow remote attackers to cause a denial of service (socket exhaustion) via unspecified network traffic.
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Analysis
by VulDB Data Team • 12/28/2024
The vulnerability identified as CVE-2011-1785 represents a critical denial of service weakness in VMware's virtualization infrastructure affecting ESXi 4.0 and 4.1 versions along with ESX 4.0 and 4.1. This flaw manifests as a socket exhaustion attack that can be executed remotely, potentially compromising the stability and availability of virtualized environments. The vulnerability falls under the broader category of resource exhaustion attacks that target fundamental networking components within virtualized systems. The unspecified nature of the network traffic pattern suggests that the attack could be triggered through various legitimate network protocols or malformed packets that exploit the underlying socket management mechanisms in the affected VMware products.
The technical implementation of this vulnerability stems from inadequate socket handling within the network stack of the affected VMware hypervisors. When processing incoming network traffic, the system fails to properly manage socket allocation and cleanup, leading to a gradual depletion of available socket resources. This condition creates a cascading effect where legitimate network operations cannot establish new connections while existing connections become unresponsive or fail. The flaw demonstrates a classic resource exhaustion pattern where attackers can systematically consume available sockets through repeated connections or by maintaining connections in states that prevent proper cleanup. This type of vulnerability aligns with CWE-400, which categorizes resource exhaustion issues as a fundamental weakness in software design that can lead to system instability and denial of service conditions.
From an operational perspective, this vulnerability presents a significant risk to organizations relying on VMware virtualization platforms, particularly in environments where continuous availability is critical. The remote exploit capability means that attackers can potentially compromise systems from external networks without requiring local access or authentication credentials. The socket exhaustion effect can render virtual machines and associated services unavailable, disrupting business operations and potentially affecting multiple virtualized workloads simultaneously. Organizations using these affected versions may experience complete network service disruption, requiring manual intervention to restore normal operations through system restarts or resource cleanup procedures. The impact extends beyond immediate service disruption to include potential data loss scenarios and extended downtime during recovery operations.
Mitigation strategies for CVE-2011-1785 should prioritize immediate patch deployment from VMware, as this represents a known vulnerability with documented exploits available in the cybersecurity community. Organizations must implement network segmentation and access controls to limit exposure to potential attackers while maintaining monitoring capabilities to detect unusual socket usage patterns. The implementation of rate limiting and connection tracking mechanisms can help prevent rapid socket consumption while maintaining legitimate service availability. Additionally, organizations should consider deploying network intrusion detection systems that can identify suspicious traffic patterns associated with socket exhaustion attacks. The vulnerability's classification under ATT&CK technique T1499.004 for network denial of service indicates that defensive measures should include monitoring for abnormal connection patterns and implementing proper connection lifecycle management. Regular security assessments and vulnerability scanning should be conducted to identify systems running affected VMware versions and ensure timely remediation across all virtualized environments.