CVE-2007-4286 in IOS
Summary
by MITRE
Buffer overflow in the Next Hop Resolution Protocol (NHRP) functionality in Cisco IOS 12.0 through 12.4 allows remote attackers to cause a denial of service (restart) and execute arbitrary code via a crafted NHRP packet.
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Analysis
by VulDB Data Team • 06/07/2025
The vulnerability described in CVE-2007-4286 represents a critical buffer overflow flaw within the Next Hop Resolution Protocol implementation in Cisco IOS software versions 12.0 through 12.4. This issue affects the network infrastructure components that rely on NHRP for dynamic routing and address resolution in multiprotocol label switching networks. The vulnerability exists in the processing of crafted NHRP packets that are designed to exceed the allocated buffer space, creating conditions that can be exploited by remote attackers without requiring authentication or privileged access.
The technical flaw manifests when the Cisco IOS software receives malformed NHRP packets that contain excessive data in specific fields of the protocol structure. This buffer overflow condition occurs because the implementation lacks proper input validation and boundary checking mechanisms for NHRP packet contents. When an attacker sends a specially crafted packet that exceeds the predetermined buffer limits, the overflow can overwrite adjacent memory locations, potentially corrupting critical system structures and execution flow. The vulnerability specifically targets the memory management routines that handle NHRP packet processing within the IOS kernel, where insufficient bounds checking allows malicious data to overwrite stack variables or function return addresses.
The operational impact of this vulnerability extends beyond simple denial of service to include potential remote code execution capabilities that could allow attackers to gain unauthorized control over affected network devices. A successful exploitation can cause immediate system restarts, leading to network disruption and service unavailability that affects all traffic passing through the compromised router or switch. In more severe scenarios, the buffer overflow may enable attackers to inject and execute arbitrary code within the router's memory space, potentially providing a foothold for further network infiltration and persistent access. This makes the vulnerability particularly dangerous in enterprise and service provider environments where these devices serve as critical network infrastructure components.
Mitigation strategies for CVE-2007-4286 should prioritize immediate deployment of Cisco's official security patches and software updates that address the buffer overflow conditions in NHRP processing. Network administrators should implement access control measures to limit exposure of affected devices to untrusted networks and consider disabling NHRP functionality when not required for specific network operations. The implementation of network segmentation and monitoring solutions can help detect anomalous NHRP packet patterns that may indicate exploitation attempts. Organizations should also review their network architecture to minimize reliance on NHRP where possible and maintain comprehensive backup and recovery procedures for critical network infrastructure. This vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a typical example of how protocol implementation flaws can create significant security risks in network operating systems. The attack surface for this vulnerability is particularly concerning given that NHRP is commonly used in enterprise and service provider networks for dynamic routing in multiprotocol label switching environments, making it a target for adversaries seeking to disrupt network communications and gain persistent access to critical infrastructure.