CVE-2015-4651 in Wireshark
Summary
by MITRE
The dissect_wccp2r1_address_table_info function in epan/dissectors/packet-wccp.c in the WCCP dissector in Wireshark 1.12.x before 1.12.6 does not properly determine whether enough memory is available for storing IP address strings, which allows remote attackers to cause a denial of service (application crash) via a crafted packet.
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Analysis
by VulDB Data Team • 06/03/2022
The vulnerability identified as CVE-2015-4651 resides within the Wireshark network protocol analyzer application, specifically within the WCCP dissector module responsible for processing WCCP version 2 revision 1 protocol data. This issue affects Wireshark versions 1.12.x prior to 1.12.6, representing a critical denial of service vulnerability that can be exploited remotely. The flaw manifests in the dissect_wccp2r1_address_table_info function which handles the parsing of address table information within WCCP packets. The vulnerability stems from inadequate memory management during the processing of IP address strings, creating a scenario where the application fails to properly validate memory allocation requirements before storing network address data.
The technical implementation of this vulnerability involves a classic buffer overflow condition that occurs when the dissector attempts to store IP address information extracted from WCCP packets. When processing maliciously crafted packets containing oversized or malformed address table information, the function fails to verify whether sufficient memory exists for the destination storage buffer. This memory validation failure results in a memory corruption condition that ultimately leads to application crash and termination. The flaw operates at the protocol dissection layer where Wireshark processes network traffic for analysis, making it particularly dangerous as it can be triggered simply by capturing and analyzing malicious network traffic without requiring any special privileges or user interaction beyond normal packet processing.
From an operational perspective, this vulnerability presents significant risks to network security analysts and forensic investigators who rely on Wireshark for network traffic analysis. An attacker can remotely trigger this denial of service condition by transmitting a specially crafted WCCP packet to a system running vulnerable Wireshark software. The impact extends beyond simple application crash, as it can disrupt ongoing network monitoring activities, compromise forensic investigations, and potentially provide attackers with a method to disrupt network analysis operations. The vulnerability is particularly concerning in environments where Wireshark is used for continuous network monitoring or security incident response activities, as it could be exploited to deny network visibility and compromise security operations.
The vulnerability aligns with CWE-129, which addresses "Improper Validation of Array Index" and specifically relates to improper handling of buffer sizes during memory allocation. From an ATT&CK framework perspective, this vulnerability maps to T1046 Network Service Scanning and T1499 Endpoint Denial of Service, as it enables remote exploitation that can disrupt network analysis services. The attack vector requires minimal privileges and can be executed through standard network traffic, making it particularly dangerous for network security professionals who may inadvertently process malicious packets during routine network analysis activities. Organizations using Wireshark for network monitoring, incident response, or security auditing are particularly vulnerable to this attack vector.
Mitigation strategies for CVE-2015-4651 focus primarily on immediate software updates to Wireshark version 1.12.6 or later, which includes the necessary patches to properly validate memory allocation during WCCP packet processing. Network administrators should also implement network segmentation and access controls to limit exposure to potentially malicious traffic, while monitoring for unusual network behavior that might indicate exploitation attempts. Additionally, organizations should consider implementing network-based intrusion detection systems that can identify and block suspicious WCCP traffic patterns. Regular vulnerability assessments and security updates should be prioritized to ensure that all network analysis tools remain protected against similar memory corruption vulnerabilities that could compromise network monitoring capabilities and security operations.