CVE-2012-6054 in Wireshark
Summary
by MITRE
The dissect_sflow_245_address_type function in epan/dissectors/packet-sflow.c in the sFlow dissector in Wireshark 1.8.x before 1.8.4 does not properly handle length calculations for an invalid IP address type, which allows remote attackers to cause a denial of service (infinite loop) via a packet that is neither IPv4 nor IPv6.
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Analysis
by VulDB Data Team • 12/20/2021
The vulnerability identified as CVE-2012-6054 resides within the sFlow dissector component of Wireshark, specifically in the dissect_sflow_245_address_type function located in epan/dissectors/packet-sflow.c. This flaw affects Wireshark versions 1.8.x prior to 1.8.4 and represents a critical denial of service vulnerability that can be exploited remotely. The issue manifests when the dissector encounters sFlow packets containing invalid IP address types that are neither IPv4 nor IPv6, creating a scenario where the parsing logic fails to properly calculate the expected packet length. This improper handling of length calculations creates a condition where the dissector enters an infinite loop during packet processing, effectively causing the application to become unresponsive and unable to process subsequent network traffic.
The technical root cause of this vulnerability stems from inadequate input validation and boundary checking within the sFlow protocol dissector implementation. When Wireshark processes sFlow packets, it attempts to identify and decode the address type contained within the packet structure, specifically looking for either IPv4 or IPv6 address formats. However, when encountering a packet where the address type field indicates a format that is neither IPv4 nor IPv6, the function fails to properly validate the length parameters associated with the address data. This validation failure allows an attacker to craft malicious sFlow packets that contain malformed address type indicators, causing the dissector to continuously loop while attempting to parse what it perceives as valid data but which actually represents an invalid state. The vulnerability is categorized under CWE-129 as an Improper Validation of Array Index, as the function does not properly validate the length calculations before proceeding with packet parsing operations.
The operational impact of this vulnerability extends beyond simple service disruption, as it can be leveraged in various attack scenarios that target network monitoring and analysis systems. Network administrators and security analysts who rely on Wireshark for traffic analysis, troubleshooting, and security monitoring are particularly vulnerable when the tool is deployed in environments where untrusted network traffic may be processed. The infinite loop condition can persist for extended periods, consuming significant system resources and potentially leading to complete system unresponsiveness if multiple malicious packets are processed in succession. This makes the vulnerability especially dangerous in network operations centers where Wireshark is used for continuous monitoring, as a single malicious packet can effectively bring down the entire analysis infrastructure. The attack vector requires only that an attacker be able to send sFlow packets to a system running the vulnerable version of Wireshark, making it particularly easy to exploit in environments where sFlow data collection is enabled.
Mitigation strategies for CVE-2012-6054 primarily focus on upgrading to the patched version of Wireshark, specifically version 1.8.4 or later, where the length calculation validation has been properly implemented. Organizations should also implement network segmentation and access controls to limit the exposure of systems running Wireshark to untrusted network traffic, particularly in environments where sFlow data is being collected. Additional defensive measures include implementing network-based intrusion detection systems that can identify and block malformed sFlow packets, as well as deploying network monitoring tools that can detect and alert on unusual resource consumption patterns that may indicate exploitation attempts. The vulnerability demonstrates the importance of proper input validation and error handling in protocol dissector implementations, as highlighted by ATT&CK technique T1070.004 for Indicator Removal on Host and T1566.002 for Phishing with Social Engineering. Network security teams should also consider implementing automated patch management processes to ensure that all network analysis tools remain up-to-date with the latest security fixes, particularly those addressing denial of service vulnerabilities that can be exploited remotely without authentication.