CVE-2001-0057 in CBOS
Summary
by MITRE
Cisco 600 routers running CBOS 2.4.1 and earlier allow remote attackers to cause a denial of service via a large ICMP echo (ping) packet.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 04/07/2019
The vulnerability identified as CVE-2001-0057 affects Cisco 600 series routers operating with CBOS version 2.4.1 and earlier releases. This represents a classic denial of service weakness that exploits the router's handling of ICMP echo requests, commonly known as ping packets. The flaw manifests when the router receives an oversized ICMP echo packet that exceeds normal network protocol boundaries, causing the device to become unresponsive or crash entirely.
This vulnerability stems from inadequate input validation within the router's ICMP processing module. The CBOS operating system fails to properly sanitize incoming ICMP echo packets, particularly those exceeding standard size limits. When such oversized packets are received, the router's memory management and packet processing routines become overwhelmed, leading to system instability and complete service disruption. The issue is particularly concerning because ICMP echo requests are fundamental network diagnostic tools that are routinely used for network connectivity testing and monitoring.
The operational impact of this vulnerability extends beyond simple service interruption to encompass broader network reliability concerns. Network administrators relying on these routers for critical infrastructure may experience unexpected outages that disrupt communication services. The remote nature of the attack means that adversaries can exploit this weakness from anywhere on the network without requiring physical access or authentication credentials. This characteristic aligns with attack patterns documented in the mitre ATT&CK framework under the T1499 category for network denial of service attacks, where adversaries target network infrastructure to disrupt availability.
From a security perspective, this vulnerability demonstrates the critical importance of proper input validation and memory management in network infrastructure devices. The flaw represents a failure in defensive programming practices that should prevent malformed packets from causing system crashes. The Common Weakness Enumeration (CWE) classification for this issue would likely fall under CWE-129, which addresses insufficient input validation, or potentially CWE-122, dealing with buffer overflow conditions that can occur when processing oversized data. Network security professionals should note that this vulnerability predates modern security hardening practices and highlights the evolution of security considerations in embedded networking systems.
Mitigation strategies for CVE-2001-0057 primarily involve upgrading the affected Cisco 600 routers to CBOS versions that address this specific vulnerability. Cisco released patches and updated firmware versions that implement proper ICMP packet size validation and memory protection mechanisms. Network administrators should also consider implementing access control lists that filter ICMP traffic or limit the size of packets allowed through the router. Additionally, network segmentation and monitoring solutions can help detect unusual ICMP traffic patterns that might indicate exploitation attempts. The vulnerability serves as a reminder of the importance of maintaining current firmware versions and implementing comprehensive network security monitoring to detect and respond to such threats effectively.