CVE-2016-8575 in macOS
Summary
by MITRE
The Q.933 parser in tcpdump before 4.9.0 has a buffer overflow in print-fr.c:q933_print(), a different vulnerability than CVE-2017-5482.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 05/16/2026
The vulnerability identified as CVE-2016-8575 represents a critical buffer overflow flaw within the Q.933 protocol parser of tcpdump network analysis tool. This issue specifically affects versions prior to 4.9.0 and occurs within the print-fr.c source file at the q933_print() function. The Q.933 protocol is part of the ITU-T recommendation for signaling messages in digital subscriber line networks, making this vulnerability particularly concerning for network infrastructure monitoring and security analysis tools that rely on tcpdump for packet inspection.
The technical implementation of this buffer overflow stems from inadequate input validation and bounds checking within the Q.933 protocol message parsing logic. When tcpdump encounters a malformed Q.933 packet during network traffic analysis, the q933_print() function fails to properly validate the size of incoming data before copying it into fixed-size buffers. This classic buffer overflow condition allows an attacker to craft malicious network packets that exceed the allocated buffer space, potentially leading to memory corruption and arbitrary code execution. The vulnerability is classified as a CWE-121 heap-based buffer overflow, representing a fundamental flaw in memory management and input handling within the network protocol parser.
From an operational perspective, this vulnerability poses significant risks to network security monitoring systems that depend on tcpdump for real-time packet analysis. Attackers could exploit this weakness by sending specially crafted Q.933 protocol messages to network devices running vulnerable versions of tcpdump, potentially compromising the integrity of network monitoring infrastructure. The impact extends beyond simple denial of service, as successful exploitation could allow attackers to execute arbitrary code with the privileges of the tcpdump process, which typically runs with elevated permissions to capture network traffic. This vulnerability aligns with ATT&CK technique T1059.007 for command and control through network protocol manipulation.
Network administrators and security professionals should prioritize immediate remediation of this vulnerability by upgrading to tcpdump version 4.9.0 or later, which includes proper bounds checking and input validation for Q.933 protocol messages. Additional mitigations include implementing network segmentation to limit exposure of vulnerable systems, deploying intrusion detection systems to monitor for suspicious Q.933 protocol traffic patterns, and conducting regular security assessments of network monitoring infrastructure. The vulnerability demonstrates the critical importance of maintaining up-to-date network security tools and highlights the need for comprehensive input validation in protocol parsing components that handle untrusted network data, particularly in security-critical applications like network traffic analysis and monitoring systems.