CVE-2018-14880 in tcpdump
Summary
by MITRE
The OSPFv3 parser in tcpdump before 4.9.3 has a buffer over-read in print-ospf6.c:ospf6_print_lshdr().
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Analysis
by VulDB Data Team • 01/03/2024
The vulnerability identified as CVE-2018-14880 represents a critical buffer over-read flaw within the OSPFv3 protocol parser of tcpdump software version 4.9.2 and earlier. This issue manifests specifically in the print-ospf6.c source file at the ospf6_print_lshdr() function, where insufficient input validation allows for memory access beyond allocated buffer boundaries. The vulnerability affects network traffic analysis tools that rely on tcpdump for packet inspection, particularly in environments where OSPFv3 routing protocols are actively used. The buffer over-read condition occurs when processing malformed OSPFv3 link-state header packets, potentially leading to unpredictable program behavior and system instability. This flaw demonstrates a classic security weakness in network protocol parsing implementations where boundary checks are inadequate for handling malformed input data.
The technical implementation of this vulnerability stems from improper handling of packet length fields within OSPFv3 link-state headers during the parsing process. When tcpdump encounters an OSPFv3 packet with a malformed header structure, the ospf6_print_lshdr() function fails to validate the actual packet size against the declared length fields in the OSPFv3 header. This discrepancy allows the parser to read memory locations beyond the intended buffer boundaries, potentially accessing uninitialized memory regions or data belonging to other program components. The vulnerability is classified under CWE-125 as an out-of-bounds read condition, which represents a fundamental flaw in input validation mechanisms. The flaw is particularly concerning because it can be triggered through network traffic without requiring any special privileges or authentication, making it a remote code execution vector when exploited in certain contexts.
The operational impact of CVE-2018-14880 extends beyond simple program crashes or memory corruption, as it can be leveraged in broader attack scenarios within network monitoring and security analysis environments. Network administrators and security analysts who rely on tcpdump for traffic analysis may find their monitoring systems compromised when processing maliciously crafted OSPFv3 packets. The vulnerability can be exploited in man-in-the-middle attacks where attackers inject malformed OSPFv3 packets into network traffic to trigger the buffer over-read condition. Additionally, the flaw affects network infrastructure monitoring systems, intrusion detection systems, and security information and event management platforms that depend on tcpdump for packet capture and analysis. This vulnerability can lead to denial of service conditions, data leakage, or potentially remote code execution depending on the specific system configuration and memory layout. The ATT&CK framework categorizes this vulnerability under T1059 Command and Scripting Interpreter and T1566 Phishing with Malicious Attachments as it can be used to compromise network monitoring infrastructure and gain unauthorized access to network traffic analysis systems.
Mitigation strategies for CVE-2018-14880 primarily focus on upgrading to tcpdump version 4.9.3 or later, which includes proper bounds checking and input validation for OSPFv3 packet parsing. Network administrators should implement network segmentation and access controls to limit exposure to potentially malicious OSPFv3 traffic, particularly in environments where OSPFv3 is not actively required. Additional protective measures include deploying network intrusion detection systems that can identify and block malformed OSPFv3 packets, implementing proper network access controls, and conducting regular vulnerability assessments of network monitoring infrastructure. Organizations should also consider implementing network traffic filtering rules that restrict OSPFv3 traffic to trusted network segments only, and establish monitoring procedures to detect unusual packet processing patterns that might indicate exploitation attempts. The vulnerability highlights the importance of maintaining up-to-date network security tools and demonstrates the critical need for thorough input validation in protocol parsing implementations. Security teams should also conduct regular security testing and penetration testing to identify similar vulnerabilities in other network protocol parsers and monitoring tools within their infrastructure.