CVE-2018-7332 in Wireshark
Summary
by MITRE
In Wireshark 2.4.0 to 2.4.4 and 2.2.0 to 2.2.12, epan/dissectors/packet-reload.c had an infinite loop that was addressed by validating a length.
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Analysis
by VulDB Data Team • 02/10/2023
The vulnerability identified as CVE-2018-7332 represents a critical software flaw discovered in Wireshark versions ranging from 2.4.0 through 2.4.4 and 2.2.0 through 2.2.12. This issue resides within the packet-reload.c file located in the epan/dissectors directory of the Wireshark codebase, highlighting a fundamental problem in the network protocol analysis tool's packet processing capabilities. The flaw manifests as an infinite loop condition that can be triggered during the analysis of specific network traffic patterns, potentially leading to system resource exhaustion and denial of service conditions.
The technical implementation of this vulnerability stems from inadequate input validation within the packet reloading functionality. When Wireshark processes certain malformed or specially crafted network packets, the code in packet-reload.c fails to properly validate the length parameters associated with packet data structures. This validation gap creates a scenario where the loop counter or iteration mechanism continues indefinitely, as the program cannot properly determine when to terminate the processing cycle. The flaw operates at the protocol dissection layer, which is critical for network traffic analysis, making it particularly dangerous as it can be exploited through the analysis of captured network traffic files or live packet captures.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as it can affect the reliability and availability of network analysis operations. When an attacker can trigger this infinite loop, they effectively cause the Wireshark application to consume excessive CPU resources or become unresponsive, potentially disrupting network monitoring and troubleshooting activities. This vulnerability particularly affects network security professionals and analysts who rely on Wireshark for critical infrastructure monitoring, as the tool may become unavailable during important investigations or security events. The issue can also impact automated network analysis systems that depend on Wireshark's stability and performance.
The remediation for CVE-2018-7332 involved implementing proper length validation mechanisms within the packet-reload.c file, ensuring that all packet length parameters are properly checked before entering iterative processing loops. This fix aligns with established security practices and follows the principle of input validation that is fundamental to preventing many classes of software vulnerabilities. The vulnerability can be mapped to CWE-835, which describes the weakness of an infinite loop or infinite recursion, and demonstrates the importance of proper boundary checking in protocol analysis software. From an attack mitigation perspective, this vulnerability aligns with ATT&CK technique T1489, which involves denying access to systems through resource exhaustion, although the specific implementation focuses on application-level resource consumption rather than system-level attacks.
Network security practitioners should prioritize updating their Wireshark installations to versions that contain the patched code, as the vulnerability can be exploited through various attack vectors including malicious packet captures or network traffic manipulation. The fix implemented addresses the root cause by ensuring that packet length validation occurs before any iterative processing begins, preventing the conditions that lead to the infinite loop scenario. Organizations using Wireshark for network monitoring should also consider implementing additional safeguards such as resource limits on packet processing and monitoring for unusual CPU consumption patterns that might indicate exploitation attempts. The vulnerability serves as a reminder of the critical importance of input validation in network analysis tools and the potential consequences of insufficient bounds checking in protocol dissection code.