CVE-2004-1776 in IOS
Summary
by MITRE
Cisco IOS 12.1(3) and 12.1(3)T allows remote attackers to read and modify device configuration data via the cable-docsis read-write community string used by the Data Over Cable Service Interface Specification (DOCSIS) standard.
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Analysis
by VulDB Data Team • 11/21/2024
The vulnerability identified as CVE-2004-1776 represents a critical security flaw in Cisco IOS software versions 12.1(3) and 12.1(3)T that affects devices implementing the Data Over Cable Service Interface Specification standard. This issue stems from improper access controls within the DOCSIS implementation, specifically exposing a read-write community string that should not be accessible to unauthorized remote parties. The flaw exists in the cable-docsis functionality that manages communication between cable modems and cable modem termination systems, creating an unauthorized access vector that bypasses normal authentication mechanisms.
The technical exploitation of this vulnerability occurs through the manipulation of the DOCSIS protocol implementation within Cisco IOS. Attackers can leverage the exposed read-write community string to establish unauthorized communication sessions with the affected devices, gaining the ability to both read sensitive configuration data and modify device settings remotely. This represents a significant privilege escalation vulnerability as the community string provides administrative-level access to network configuration parameters that control the device's operational behavior and security policies. The vulnerability specifically affects the cable-docsis subsystem where the community string is implemented without proper access control enforcement.
The operational impact of this vulnerability extends beyond simple unauthorized access to encompass potential network disruption and security compromise. Remote attackers can modify critical network configuration parameters, potentially leading to service degradation, unauthorized network access, or complete device control. The exposure of configuration data allows attackers to gather intelligence about network topology, security settings, and operational parameters that could be used for further attacks. This vulnerability particularly impacts cable modem termination systems and other network infrastructure components that rely on DOCSIS standards for cable modem management and configuration.
Mitigation strategies for CVE-2004-1776 should focus on immediate patch application and network segmentation. Cisco released IOS software updates addressing this vulnerability, and administrators should prioritize upgrading to patched versions of IOS software. Network segmentation through firewall rules and access control lists can help limit exposure of affected devices to untrusted networks. Additionally, implementing strong authentication mechanisms and disabling unnecessary services can reduce the attack surface. The vulnerability aligns with CWE-284 access control weaknesses and represents a typical example of privilege escalation through improper access control implementation. Organizations should also consider implementing network monitoring to detect unauthorized configuration changes and establish baseline network configurations to quickly identify potential compromise.
This vulnerability demonstrates the importance of proper access control implementation in network protocol stacks and highlights the risks associated with legacy DOCSIS implementations in enterprise networking equipment. The issue represents a fundamental failure in the principle of least privilege, where administrative functionality was exposed without proper authentication checks. Security practitioners should examine similar implementations across other network protocols and ensure that all community strings and administrative interfaces are properly secured. The vulnerability also underscores the necessity of regular security assessments and prompt patch management to address known weaknesses in network infrastructure software.