CVE-2017-13036 in macOS
Summary
by MITRE
The OSPFv3 parser in tcpdump before 4.9.2 has a buffer over-read in print-ospf6.c:ospf6_decode_v3().
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Analysis
by VulDB Data Team • 09/08/2024
The vulnerability identified as CVE-2017-13036 represents a critical buffer over-read flaw within the OSPFv3 parsing functionality of tcpdump version 4.9.1 and earlier. This issue resides specifically in the print-ospf6.c source file at the ospf6_decode_v3() function, where insufficient input validation allows maliciously crafted OSPFv3 packets to trigger unauthorized memory access patterns. The vulnerability occurs during the parsing of Open Shortest Path First version 3 protocol packets, which are essential for IPv6 network routing operations and widely deployed in enterprise and service provider environments.
The technical implementation of this flaw stems from inadequate boundary checking within the OSPFv3 packet decoder. When tcpdump processes incoming OSPFv3 packets, the ospf6_decode_v3() function attempts to read beyond the allocated buffer boundaries without proper validation of packet length or structure. This over-read condition can be exploited by an attacker who crafts specially malformed OSPFv3 packets that contain unexpected data lengths or malformed headers. The vulnerability manifests as a memory access violation that can potentially lead to information disclosure, denial of service, or in some scenarios, arbitrary code execution depending on the system's memory layout and the attacker's ability to control the over-read data.
From an operational impact perspective, this vulnerability poses significant risks to network infrastructure that relies on tcpdump for network monitoring and analysis. Network administrators who deploy tcpdump for traffic analysis, intrusion detection, or network troubleshooting may find their systems compromised when processing malicious OSPFv3 traffic. The attack vector is particularly concerning because OSPFv3 is commonly used in enterprise networks, and the vulnerability can be triggered simply by capturing network traffic containing maliciously crafted packets. The flaw affects systems where tcpdump is actively monitoring OSPFv3 traffic, making it a persistent threat in environments where network monitoring is critical for security operations.
The vulnerability aligns with CWE-125, which describes out-of-bounds read conditions in software implementations, and represents a classic example of improper input validation in network protocol parsers. From an ATT&CK framework perspective, this vulnerability maps to T1046 for network service scanning and T1566 for malicious code injection, as attackers could leverage this flaw to gain unauthorized access to monitoring systems or disrupt network operations. The exploitability of this vulnerability is enhanced in environments where tcpdump is used in network monitoring appliances or security tools that automatically process captured packets without proper input sanitization.
Mitigation strategies for CVE-2017-13036 primarily involve upgrading to tcpdump version 4.9.2 or later, which contains the patched ospf6_decode_v3() function with proper boundary checks and input validation. Network administrators should also implement network segmentation and access controls to limit exposure to potentially malicious OSPFv3 traffic, particularly in environments where tcpdump is used for packet capture and analysis. Additionally, deploying intrusion detection systems that can identify and block malformed OSPFv3 packets can provide an additional layer of protection while waiting for the software upgrade. Regular security assessments and network monitoring should include checks for tcpdump versions in use to ensure compliance with security patches and minimize the risk of exploitation through this buffer over-read vulnerability.