CVE-2009-3551 in Wireshark
Summary
by MITRE
Off-by-one error in the dissect_negprot_response function in packet-smb.c in the SMB dissector in Wireshark 1.2.0 through 1.2.2 allows remote attackers to cause a denial of service (application crash) via a file that records a malformed packet trace. NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 08/24/2021
The vulnerability described in CVE-2009-3551 represents a critical off-by-one error within the SMB dissector component of Wireshark versions 1.2.0 through 1.2.2. This flaw exists in the dissect_negprot_response function located in the packet-smb.c file, which is responsible for parsing SMB negotiation protocol responses during packet analysis. The issue arises when Wireshark processes malformed packet traces that contain improperly formatted SMB negotiation responses, creating a condition where buffer boundaries are incorrectly handled during protocol parsing operations.
The technical nature of this vulnerability stems from improper bounds checking within the dissector logic, specifically when processing the length field of SMB negotiation responses. An off-by-one error occurs when the application attempts to access memory locations beyond the allocated buffer boundaries, typically due to incorrect loop termination conditions or boundary calculations. This type of flaw falls under CWE-129, which encompasses improper validation of array indices, and represents a classic example of buffer overflow conditions that can lead to application instability. When a remote attacker crafts a specially formatted packet trace file containing malformed SMB negotiation data, the dissector fails to properly validate input parameters before processing them, resulting in memory corruption that ultimately causes the application to crash.
The operational impact of this vulnerability extends beyond simple denial of service, as it creates a potential attack vector that could be exploited in various network monitoring and forensic analysis scenarios. Network security professionals who rely on Wireshark for protocol analysis and troubleshooting may find their monitoring tools becoming unstable when processing legitimate network traffic that contains malformed SMB packets, particularly in environments where network traffic is captured and analyzed for security purposes. The vulnerability affects the core functionality of Wireshark's protocol dissection capabilities, meaning that even legitimate packet captures could trigger application crashes, potentially disrupting critical network monitoring operations and forensic investigations. This makes the vulnerability particularly dangerous in enterprise environments where Wireshark is commonly used for network troubleshooting and security analysis.
Mitigation strategies for this vulnerability should focus on immediate version upgrades to Wireshark 1.2.3 or later, which contains the necessary patches to address the off-by-one error in the SMB dissector. Organizations should also implement network segmentation and access controls to limit exposure to potentially malicious packet traces, while maintaining strict input validation procedures for any packet capture files processed through network analysis tools. Security teams should consider implementing automated monitoring for application stability and crash reporting to detect potential exploitation attempts. The ATT&CK framework categorizes this vulnerability under T1498, which covers network denial of service attacks, and T1566, which encompasses malicious file execution techniques. Additionally, this vulnerability highlights the importance of proper input validation and memory management practices in network protocol analysis tools, emphasizing the need for robust testing procedures including fuzzing and boundary condition testing to prevent similar issues in other dissector components.