CVE-2006-3632 in Wireshark
Summary
by MITRE
Buffer overflow in Wireshark (aka Ethereal) 0.8.16 to 0.99.0 allows remote attackers to cause a denial of service and possibly execute arbitrary code via the NFS dissector.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 06/23/2019
The vulnerability identified as CVE-2006-3632 represents a critical buffer overflow flaw within Wireshark's Network File System (NFS) dissector component. This issue affects versions 0.8.16 through 0.99.0 of the popular network protocol analyzer, creating a significant security risk for users who process network traffic containing NFS protocol data. The buffer overflow occurs when the dissector attempts to parse malformed or specially crafted NFS packets, leading to potential system compromise and service disruption. This vulnerability falls under the Common Weakness Enumeration category CWE-121, which specifically addresses stack-based buffer overflow conditions that can result in arbitrary code execution or denial of service attacks. The flaw demonstrates a classic example of unsafe memory handling practices in network protocol analysis tools where insufficient input validation allows attackers to manipulate memory structures through crafted packet data.
The technical exploitation of this vulnerability requires an attacker to craft malicious NFS packets that trigger the buffer overflow condition within Wireshark's dissector module. When the application processes these malformed packets, the insufficient bounds checking in the NFS dissector causes memory corruption that can lead to stack smashing or heap corruption. This type of vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter, as successful exploitation could enable arbitrary code execution on the victim system. The buffer overflow specifically affects the dissector's ability to properly parse NFS version 2 and 3 packet structures, where the application fails to validate the length of data fields before copying them into fixed-size buffers. The memory corruption can manifest as application crashes, denial of service conditions, or in more severe cases, complete system compromise when the attacker can control the execution flow through carefully crafted input data.
The operational impact of CVE-2006-3632 extends beyond simple denial of service scenarios, as it represents a potential path for remote code execution in environments where Wireshark is used to analyze network traffic from untrusted sources. Network administrators and security professionals who rely on Wireshark for traffic analysis, forensic investigations, or network monitoring are particularly vulnerable when processing NFS traffic from external networks or compromised systems. The vulnerability is especially concerning in environments where automated network monitoring systems continuously capture and analyze traffic, as a single malicious NFS packet could cause widespread service disruption across multiple systems. Organizations using Wireshark for security auditing, penetration testing, or incident response activities face significant risk, as the tool itself becomes a potential attack vector for adversaries seeking to compromise security infrastructure. The vulnerability also impacts the broader network security ecosystem, as compromised Wireshark installations could serve as a foothold for further attacks or as a means to evade detection by corrupting network analysis data.
Mitigation strategies for CVE-2006-3632 should focus on immediate version upgrades to Wireshark 0.99.1 or later, which contain patches addressing the buffer overflow in the NFS dissector. Network administrators should implement network segmentation and access controls to limit exposure to potentially malicious NFS traffic, particularly in environments where untrusted network data is processed. The implementation of network monitoring solutions that can detect and block suspicious NFS traffic patterns provides additional defense layers. Security teams should consider disabling the NFS dissector when analyzing untrusted traffic, as this removes the attack surface while maintaining core protocol analysis capabilities for trusted network segments. Regular security updates and patch management processes should be enforced across all network monitoring infrastructure, with particular attention to protocol dissector components that handle complex data structures. Organizations should also implement network traffic filtering rules to prevent NFS traffic from entering sensitive network segments, reducing the overall risk exposure associated with this vulnerability. The incident response plan should include procedures for identifying and isolating compromised Wireshark installations, as well as establishing baseline network behavior to detect anomalous traffic patterns that may indicate exploitation attempts.