CVE-2019-0698 in Windows
Summary
by MITRE
A memory corruption vulnerability exists in the Windows DHCP client when an attacker sends specially crafted DHCP responses to a client, aka 'Windows DHCP Client Remote Code Execution Vulnerability'. This CVE ID is unique from CVE-2019-0697, CVE-2019-0726.
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Analysis
by VulDB Data Team • 07/31/2023
The vulnerability described in CVE-2019-0698 represents a critical memory corruption flaw within the Windows Dynamic Host Configuration Protocol client implementation that can be exploited remotely by attackers. This vulnerability specifically affects the Windows DHCP client component responsible for processing DHCP responses from network servers, creating a pathway for remote code execution when legitimate DHCP servers are compromised or when attackers impersonate legitimate DHCP servers within the network. The flaw stems from inadequate input validation and memory handling within the DHCP client's response processing logic, where maliciously crafted DHCP packets can cause buffer overflows or other memory corruption conditions that lead to arbitrary code execution.
The technical implementation of this vulnerability involves the Windows DHCP client's failure to properly validate DHCP response parameters before processing them in memory. When a client receives a DHCP response containing malformed or specially crafted options, the parsing logic does not adequately check bounds or validate data integrity, resulting in memory corruption that can be leveraged by attackers to execute malicious code with the privileges of the affected user. This type of vulnerability falls under the CWE-121 CWE category for stack-based buffer overflow, though the specific implementation likely involves heap-based corruption due to the nature of DHCP client memory management. The attack vector requires the attacker to be in a position to send malicious DHCP responses to a target system, typically within the same network segment or through network interception techniques.
The operational impact of this vulnerability extends beyond simple remote code execution as it provides attackers with persistent access to compromised systems and enables further lateral movement within networks. Once successfully exploited, the vulnerability allows attackers to execute arbitrary code with the privileges of the user context running the DHCP client service, potentially leading to complete system compromise. The vulnerability affects Windows systems running various versions including Windows 10, Windows Server 2016, and Windows Server 2019, making it particularly dangerous in enterprise environments where DHCP is commonly used for network management. Attackers can leverage this vulnerability to establish persistence, exfiltrate data, or use the compromised system as a launch point for attacks against other network resources.
Mitigation strategies for CVE-2019-0698 should include immediate deployment of Microsoft security patches as the primary defense mechanism, combined with network segmentation to limit the scope of potential attacks. Organizations should implement DHCP snooping and DHCP server authentication mechanisms to prevent unauthorized DHCP servers from operating on the network, while also monitoring for unusual DHCP traffic patterns that might indicate exploitation attempts. Network administrators should consider disabling DHCP client functionality on systems where it is not required, and implement proper network access controls to limit which systems can communicate with DHCP servers. The vulnerability's exploitation requires network-level access, making network monitoring and intrusion detection systems crucial for early identification of potential attacks, while following the ATT&CK framework's T1071.004 technique for application layer protocol usage in network communication monitoring. Additionally, regular security assessments and vulnerability scanning should be conducted to identify systems running vulnerable versions of Windows that require patching or other compensating controls.