CVE-2009-3550 in Wireshark
Summary
by MITRE
The DCERPC/NT dissector in Wireshark 0.10.10 through 1.0.9 and 1.2.0 through 1.2.2 allows remote attackers to cause a denial of service (NULL pointer dereference and 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 identified as CVE-2009-3550 represents a critical denial of service flaw within Wireshark's DCERPC/NT dissector component. This security issue affects multiple versions of the popular network protocol analyzer, specifically targeting releases from 0.10.10 through 1.0.9 and 1.2.0 through 1.2.2. The flaw manifests when Wireshark processes packet capture files containing malformed DCERPC/NT traffic, creating a scenario where legitimate network analysis operations can be disrupted through carefully crafted malicious input. The vulnerability operates at the application layer of network traffic analysis, leveraging the dissector's inability to properly handle malformed data structures that are commonly encountered in distributed computing environment communications.
The technical implementation of this vulnerability stems from a NULL pointer dereference condition within the DCERPC/NT protocol dissector module. When Wireshark encounters a malformed packet trace file containing DCERPC/NT data, the dissector fails to validate the structure of incoming data before attempting to access memory locations. This improper validation leads to a situation where the application attempts to dereference a null pointer, causing an immediate application crash and termination of the network analysis session. The flaw is classified under CWE-476 as a NULL Pointer Dereference, which represents a common programming error where code assumes a pointer will not be null without proper validation checks. The vulnerability demonstrates how protocol analysis tools can become attack vectors themselves when they fail to implement robust input sanitization mechanisms.
The operational impact of this vulnerability extends beyond simple service disruption, as it can be exploited remotely through malicious packet capture files. Attackers can craft specially formatted .pcap files containing malformed DCERPC/NT traffic that, when opened in affected Wireshark versions, will trigger the NULL pointer dereference and subsequent application crash. This creates a significant risk for network administrators and security professionals who rely on Wireshark for network monitoring and incident response activities, as simply opening a compromised packet capture file could compromise their analysis capabilities. The vulnerability affects the availability aspect of network security operations, as it can be used to deny network analysts access to critical traffic analysis tools during important investigations or security events.
Mitigation strategies for CVE-2009-3550 primarily involve immediate version upgrades to patched releases of Wireshark, specifically versions 1.0.10 and 1.2.3 or later where the dissector has been updated to properly validate input data structures. Network security teams should implement strict file validation policies for packet capture files, particularly when dealing with externally provided traffic data. The vulnerability aligns with ATT&CK technique T1070.004 which covers the use of file and directory permissions to prevent unauthorized access, though in this case the attack vector involves legitimate file opening operations. Organizations should also consider implementing network traffic analysis sandboxing mechanisms to isolate potentially malicious packet data and prevent direct exposure to vulnerable applications. Additionally, the incident highlights the importance of input validation in protocol analysis tools and demonstrates how protocol dissectors must be rigorously tested against malformed data to prevent similar vulnerabilities from being exploited in production environments.