CVE-2017-12992 in macOS
Summary
by MITRE
The RIPng parser in tcpdump before 4.9.2 has a buffer over-read in print-ripng.c:ripng_print().
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Analysis
by VulDB Data Team • 12/05/2025
The vulnerability identified as CVE-2017-12992 represents a critical buffer over-read flaw within the RIPng (Routing Information Protocol next generation) parser implementation of tcpdump version 4.9.1 and earlier. This issue resides in the print-ripng.c source file at the ripng_print() function, where insufficient input validation allows maliciously crafted network packets to trigger unauthorized memory access patterns. The vulnerability specifically affects the parsing of RIPng packets which are used in IPv6 routing protocols to exchange routing information between network devices. When tcpdump processes malformed RIPng packets, the parser fails to properly bounds-check buffer boundaries during packet content traversal, leading to memory access beyond allocated buffer limits.
The technical exploitation of this vulnerability occurs when tcpdump encounters specially crafted RIPng packets that contain unexpected packet structures or malformed data fields. The ripng_print() function does not adequately validate the length of incoming packet data before attempting to read from memory locations that may extend beyond the actual packet boundaries. This over-read condition can result in the program accessing uninitialized memory regions, potentially exposing sensitive data from adjacent memory locations or causing application instability. The flaw demonstrates characteristics consistent with CWE-125, which describes out-of-bounds read vulnerabilities where programs access memory beyond the intended buffer limits. From an operational perspective, this vulnerability could enable attackers to either extract confidential information from memory or cause denial of service conditions within network monitoring systems that rely on tcpdump for packet analysis.
Network security operations are significantly impacted by this vulnerability as it affects network monitoring and forensic analysis capabilities. When exploited, the buffer over-read can cause tcpdump to crash or behave unpredictably during packet capture sessions, potentially leading to loss of critical network monitoring data. This is particularly concerning in environments where tcpdump is used for security auditing, intrusion detection, or network troubleshooting activities. The vulnerability aligns with ATT&CK technique T1046 which involves network service scanning and can be leveraged by adversaries to gain information about network topology through malformed packet injection. Organizations using tcpdump for network analysis may experience service disruption or information leakage when processing maliciously crafted RIPng packets, especially in environments where automated monitoring systems process untrusted network traffic without proper input sanitization. The impact extends beyond simple application crashes to potential information disclosure scenarios where adjacent memory contents might be exposed through the over-read condition.
Mitigation strategies for CVE-2017-12992 primarily involve upgrading to tcpdump version 4.9.2 or later, which contains the necessary patch to address the buffer over-read condition in the RIPng parser. System administrators should prioritize patching network monitoring infrastructure that utilizes tcpdump for packet capture and analysis operations. Additional protective measures include implementing network segmentation to limit exposure to potentially malicious RIPng traffic, deploying network access control lists to filter suspicious packet patterns, and establishing robust input validation procedures for all packet parsing components. Organizations should also consider implementing network monitoring solutions that can detect and alert on anomalous packet structures that might indicate exploitation attempts. The vulnerability demonstrates the importance of maintaining up-to-date network security tools and implementing defense-in-depth strategies that include multiple layers of packet validation and monitoring to prevent exploitation of similar buffer-related vulnerabilities in network analysis tools.