CVE-2002-0115 in Snort
Summary
by MITRE
Snort 1.8.3 does not properly define the minimum ICMP header size, which allows remote attackers to cause a denial of service (crash and core dump) via a malformed ICMP packet.
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Analysis
by VulDB Data Team • 12/22/2024
The vulnerability identified as CVE-2002-0115 affects Snort version 1.8.3, a widely used network intrusion detection system that operates by analyzing network traffic for suspicious patterns and potential security threats. This flaw resides in Snort's handling of Internet Control Message Protocol packets, which are essential for network diagnostics and error reporting in ip-based networks. The issue stems from an inadequate implementation of ICMP header validation that fails to properly enforce minimum header size requirements, creating a critical gap in the software's packet parsing logic.
The technical flaw manifests when Snort encounters malformed ICMP packets that do not conform to the expected minimum header structure. During normal operation, Snort parses incoming network packets and extracts relevant header information to determine packet type and content. However, in this specific case, the software's ICMP parser does not validate that incoming packets contain sufficient header data to be processed correctly. When malformed packets with truncated or improperly formatted headers are received, Snort attempts to process them without proper boundary checks, leading to memory access violations and subsequent system instability.
This vulnerability creates a significant operational impact by enabling remote attackers to execute a denial of service attack against Snort-based systems. The attack requires only the transmission of specially crafted ICMP packets to the target system running Snort 1.8.3, making it particularly dangerous as it can be performed from any remote location without requiring authentication or special privileges. Upon receiving the malformed packet, the Snort daemon crashes and generates a core dump file, effectively rendering the intrusion detection system inoperative and eliminating network monitoring capabilities for the duration of the attack.
The root cause of this vulnerability aligns with CWE-129, which addresses improper validation of input ranges, and CWE-128, which covers issues related to buffer under-read conditions. From an attack framework perspective, this vulnerability maps to the ATT&CK technique T1498, specifically targeting network denial of service attacks. The flaw represents a classic buffer overflow condition where insufficient input validation leads to memory corruption, as the system attempts to access memory locations that may not contain valid data. The vulnerability also reflects poor defensive programming practices that fail to implement proper boundary checking and input sanitization mechanisms.
Mitigation strategies for CVE-2002-0115 include immediate deployment of the patched Snort version 1.8.4, which properly implements ICMP header size validation and includes additional input sanitization measures. Organizations should also implement network segmentation and access controls to limit exposure of Snort systems to untrusted networks, while monitoring for anomalous ICMP traffic patterns that might indicate exploitation attempts. Additional protective measures include configuring network firewalls to filter suspicious ICMP traffic and implementing intrusion prevention systems that can detect and block malformed packets before they reach the Snort daemon. System administrators should also establish robust monitoring and alerting procedures to quickly identify when Snort services become unavailable due to this type of attack.