CVE-2005-4459 in Workstation
Summary
by MITRE
Heap-based buffer overflow in the NAT networking components vmnat.exe and vmnet-natd in VMWare Workstation 5.5, GSX Server 3.2, ACE 1.0.1, and Player 1.0 allows remote authenticated attackers, including guests, to execute arbitrary code via crafted (1) EPRT and (2) PORT FTP commands.
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Analysis
by VulDB Data Team • 01/24/2025
The vulnerability identified as CVE-2005-4459 represents a critical heap-based buffer overflow affecting VMware's network virtualization components. This flaw exists within the vmnat.exe and vmnet-natd processes that handle network address translation functionality in VMware Workstation 5.5, GSX Server 3.2, ACE 1.0.1, and Player 1.0 products. The vulnerability specifically targets the handling of FTP control commands, making it particularly dangerous in environments where network services are exposed to untrusted users or guest operating systems. The affected components operate at a privileged level within the virtualization stack, creating a significant attack surface that could be exploited by malicious actors with network access.
The technical implementation of this vulnerability stems from inadequate input validation within the FTP command parsing logic of VMware's NAT networking components. When processing EPRT (Extended PORT) and PORT FTP commands, the affected software fails to properly validate the length of incoming data buffers before copying them into fixed-size heap-allocated memory regions. This classic buffer overflow condition occurs because the software does not enforce bounds checking on user-supplied FTP command parameters, allowing attackers to craft malicious command sequences that exceed the allocated buffer space. The heap-based nature of the overflow means that memory corruption occurs in dynamically allocated regions rather than on the stack, potentially leading to more complex exploitation scenarios including memory layout manipulation and bypass of certain security mitigations.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it enables remote authenticated attackers to execute arbitrary code with the privileges of the affected VMware processes. This capability allows attackers who can send FTP commands to the virtualized network components to gain complete control over the host system running VMware software. The vulnerability is particularly concerning because it can be exploited by guest operating systems running within the VMware environment, effectively breaking the isolation boundaries that virtualization platforms are designed to maintain. Attackers can leverage this vulnerability to establish persistent backdoors, escalate privileges, or use the compromised system as a launch point for further attacks against the broader network infrastructure. The exploitation requires only authenticated access to the network services, making it accessible to anyone with network connectivity to the affected virtual machines.
Mitigation strategies for CVE-2005-4459 should focus on immediate patching of affected VMware products to address the buffer overflow conditions in the NAT networking components. Organizations should implement network segmentation to limit access to virtualized environments and disable unnecessary FTP services within virtual machines. The use of network monitoring tools can help detect anomalous FTP command sequences that may indicate exploitation attempts. Additionally, implementing proper access controls and privilege separation can reduce the potential impact of successful exploitation. Security professionals should consider applying the principle of least privilege to virtualization components and regularly audit network configurations to ensure that only authorized users can access the vulnerable FTP handling functionality. This vulnerability aligns with CWE-121 heap-based buffer overflow and maps to attack techniques in the MITRE ATT&CK framework under process injection and privilege escalation categories.