CVE-2017-13018 in macOS
Summary
by MITRE
The PGM parser in tcpdump before 4.9.2 has a buffer over-read in print-pgm.c:pgm_print().
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Analysis
by VulDB Data Team • 09/08/2024
The vulnerability identified as CVE-2017-13018 represents a critical buffer over-read flaw within the Packet Generator Message (PGM) parser of tcpdump software version 4.9.2 and earlier. This issue specifically resides in the print-pgm.c source file at the pgm_print() function, where insufficient input validation and boundary checking allows for unauthorized memory access patterns. The flaw occurs when tcpdump processes network packets containing PGM protocol data, creating a scenario where the parser attempts to read memory locations beyond the allocated buffer boundaries. This type of vulnerability falls under the category of memory safety issues and is classified as CWE-125, which describes an out-of-bounds read condition that can lead to information disclosure, system instability, or potential remote code execution depending on the attack vector and system configuration.
The operational impact of this vulnerability extends beyond simple data corruption, as it creates opportunities for attackers to exploit the buffer over-read condition for information gathering and system reconnaissance. When tcpdump encounters malformed PGM packets, the parser fails to properly validate the packet structure before attempting to process its contents, leading to memory access violations that may expose sensitive data from adjacent memory regions. This vulnerability aligns with ATT&CK technique T1059.007, which involves the use of system services to execute commands, as attackers could potentially leverage this flaw to gain insights into system memory layouts or extract confidential information. The flaw particularly affects network monitoring and security analysis environments where tcpdump is commonly deployed for packet capture and analysis purposes.
Mitigation strategies for CVE-2017-13018 should prioritize immediate software updates to tcpdump version 4.9.2 or later, which includes patches specifically addressing the buffer over-read condition in the PGM parser. Organizations should also implement network segmentation and access controls to limit exposure to potentially malicious packet traffic, while monitoring for anomalous network behavior that might indicate exploitation attempts. Security teams should conduct comprehensive vulnerability assessments to identify systems running vulnerable versions of tcpdump and ensure proper patch management procedures are in place. The remediation process should include thorough testing of patched versions in controlled environments before widespread deployment, as network analysis tools like tcpdump are critical infrastructure components that require careful validation of updates to maintain operational integrity and prevent service disruptions during the patching process.