CVE-2015-1047 in vCenter Server
Summary
by MITRE
vpxd in VMware vCenter Server 5.0 before u3e, 5.1 before u3, and 5.5 before u2 allows remote attackers to cause a denial of service via a long heartbeat message.
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Analysis
by VulDB Data Team • 06/20/2022
The vulnerability identified as CVE-2015-1047 affects VMware vCenter Server's vpxd service component, which serves as the core management service for VMware vSphere environments. This issue represents a classic denial of service weakness that can be exploited remotely by attackers to disrupt critical infrastructure operations. The vulnerability specifically targets version ranges including vCenter Server 5.0 before update 3e, 5.1 before update 3, and 5.5 before update 2, indicating this was a long-standing issue affecting multiple major releases of VMware's virtualization management platform. The flaw manifests when the vpxd service receives a malformed heartbeat message that exceeds normal operational parameters, causing the service to crash or become unresponsive.
The technical nature of this vulnerability stems from inadequate input validation within the heartbeat message processing mechanism of vpxd. Heartbeat messages are routinely used in distributed systems to maintain connection integrity and service availability, but in this case the system fails to properly validate the length of incoming heartbeat data. When an attacker sends a heartbeat message that exceeds predetermined buffer limits, the vpxd service experiences a memory corruption or buffer overflow condition that results in service termination. This behavior aligns with CWE-121, which describes heap-based buffer overflow conditions, and represents a fundamental flaw in the service's defensive programming practices. The vulnerability operates at the application layer and requires no authentication, making it particularly dangerous as it can be exploited by any remote attacker with network access to the vCenter Server.
The operational impact of CVE-2015-1047 extends far beyond simple service disruption, as vCenter Server serves as the central management point for VMware vSphere environments. When the vpxd service becomes unavailable, administrators lose the ability to manage virtual machines, monitor resource utilization, and perform critical maintenance operations across their entire virtual infrastructure. This disruption can cascade into broader business impacts including virtual machine downtime, inability to perform disaster recovery operations, and potential service level agreement violations for organizations relying on VMware virtualization. The vulnerability also creates opportunities for attackers to conduct prolonged denial of service attacks, potentially causing extended outages that can last from minutes to hours depending on system recovery mechanisms. From an attack methodology perspective, this vulnerability maps to ATT&CK technique T1499.004, which covers network denial of service attacks, and represents a common exploitation pattern where attackers leverage protocol implementation weaknesses to compromise availability.
Organizations affected by this vulnerability should prioritize immediate patching of their vCenter Server installations to the latest available updates that address the heartbeat message validation issue. VMware released patches specifically addressing this vulnerability in updates 3e for vCenter 5.0, update 3 for vCenter 5.1, and update 2 for vCenter 5.5. Beyond patching, network segmentation strategies should be implemented to limit exposure of vCenter Server to untrusted networks, and monitoring systems should be enhanced to detect unusual heartbeat traffic patterns that might indicate exploitation attempts. Security teams should also consider implementing intrusion detection systems capable of identifying malformed heartbeat messages and establishing automated alerting mechanisms for service availability monitoring. The vulnerability highlights the importance of proper input validation and buffer management in critical infrastructure services, serving as a reminder that seemingly benign protocol features like heartbeat mechanisms can become attack vectors when not properly secured against malformed inputs.