CVE-2004-0460 in DHCP
Summary
by MITRE
Buffer overflow in the logging capability for the DHCP daemon (DHCPD) for ISC DHCP 3.0.1rc12 and 3.0.1rc13 allows remote attackers to cause a denial of service (server crash) and possibly execute arbitrary code via multiple hostname options in (1) DISCOVER, (2) OFFER, (3) REQUEST, (4) ACK, or (5) NAK messages, which can generate a long string when writing to a log file.
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Analysis
by VulDB Data Team • 11/19/2024
The vulnerability described in CVE-2004-0460 represents a critical buffer overflow flaw within the Internet Systems Consortiums DHCP daemon implementation. This issue specifically affects ISC DHCP versions 3.0.1rc12 and 3.0.1rc13, where the logging subsystem fails to properly validate input lengths when processing hostname options in various DHCP message types. The flaw operates through the manipulation of DHCP client-server communication protocols, exploiting the way the daemon handles logging of network traffic containing maliciously crafted hostname data. The buffer overflow occurs when the DHCP daemon processes multiple hostname options within DISCOVER, OFFER, REQUEST, ACK, or NAK messages, creating conditions where log file entries exceed allocated buffer boundaries.
The technical execution of this vulnerability leverages the inherent structure of DHCP message processing where hostname information is collected and subsequently logged for administrative purposes. When attackers craft DHCP messages containing excessively long hostname strings within the specified message types, the logging function fails to enforce proper bounds checking on the buffer allocated for storing this information. This condition results in memory corruption that can manifest as either a server crash or potentially arbitrary code execution, depending on the specific memory layout and exploitation circumstances. The vulnerability operates at the application layer and requires network access to exploit, making it particularly dangerous in environments where DHCP servers are exposed to untrusted networks.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as it represents a potential pathway for remote code execution within affected systems. Network administrators responsible for DHCP infrastructure face significant risks when systems run vulnerable versions of ISC DHCP, as attackers could leverage this flaw to compromise entire network operations. The vulnerability affects the core functionality of DHCP services, which are fundamental to network connectivity, potentially causing widespread disruption. Organizations with large network infrastructures relying on ISC DHCP servers may experience cascading failures when this vulnerability is exploited, particularly in environments where DHCP servers serve as critical infrastructure components for dynamic IP address allocation and network configuration management.
Mitigation strategies for CVE-2004-0460 require immediate patching of affected ISC DHCP installations to versions that address the buffer overflow in logging functionality. System administrators should implement network segmentation to limit access to DHCP servers from untrusted networks, reducing the attack surface available to potential exploiters. Additionally, monitoring of DHCP traffic for anomalous hostname lengths and implementing intrusion detection systems can help identify exploitation attempts. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a classic example of improper input validation in network protocol implementations. Organizations should also consider implementing network access control lists and firewall rules to restrict DHCP message processing to trusted clients only, while maintaining regular vulnerability assessments to identify similar issues in other network services.
This vulnerability demonstrates the critical importance of proper input validation in network protocol implementations, particularly those handling user-provided data within logging and administrative functions. The flaw highlights how seemingly benign network operations can become attack vectors when proper security boundaries are not established in application code. The exploitation of this vulnerability underscores the necessity of implementing robust defensive programming practices and comprehensive security testing for all network services, especially those handling dynamic input from potentially malicious sources. Organizations should maintain up-to-date security patches and conduct regular security assessments to identify and remediate similar buffer overflow conditions that could compromise system integrity and availability.