CVE-2022-29321 in DIR-816 A2
Summary
by MITRE • 05/10/2022
D-Link DIR-816 A2_v1.10CNB04 was discovered to contain a stack overflow via the lanip parameter in /goform/setNetworkLan.
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Analysis
by VulDB Data Team • 05/12/2022
The vulnerability identified as CVE-2022-29321 affects D-Link DIR-816 A2 routers running firmware version 1.10CNB04 and potentially other variants within the same product line. This issue represents a critical stack overflow condition that arises from improper input validation within the web interface processing logic. The specific attack vector involves the lanip parameter within the /goform/setNetworkLan endpoint, which serves as the administrative interface for configuring the router's local area network settings. The vulnerability exists in the router's web server component that handles form submissions and parameter processing without adequate bounds checking or input sanitization mechanisms.
The technical flaw manifests when an attacker submits a specially crafted lanip parameter value that exceeds the allocated stack buffer size. This condition leads to memory corruption that can overwrite adjacent stack memory locations, potentially including return addresses, function pointers, or other critical control data. The stack overflow vulnerability falls under CWE-121 which describes stack-based buffer overflow conditions where insufficient bounds checking allows an attacker to overwrite adjacent memory locations. The vulnerability is particularly dangerous because it occurs within the administrative interface of a network device, providing potential attackers with a direct path to compromise the entire router system.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable complete system compromise. An attacker who successfully exploits this stack overflow could gain arbitrary code execution privileges on the affected router, allowing for full administrative control over network traffic routing, firewall configuration changes, DNS resolution manipulation, and potential lateral movement within the network. The vulnerability affects the router's ability to maintain stable operation and could be leveraged for persistent backdoor installation, data exfiltration, or as part of larger network infiltration campaigns. From an attack perspective, this vulnerability aligns with ATT&CK technique T1059.007 for command and script interpreter execution, and T1566 for phishing with malicious attachments, as exploitation typically requires user interaction with a malicious web page or form submission.
Mitigation strategies for CVE-2022-29321 should prioritize immediate firmware updates from D-Link, as the vendor has likely released patches addressing this specific vulnerability. Network administrators should implement network segmentation and access controls to limit exposure of affected devices to untrusted networks. The implementation of web application firewalls and input validation rules can provide additional protection layers, while monitoring for unusual traffic patterns or attempted exploitation attempts should be enabled. Regular security assessments of network infrastructure should include vulnerability scanning for similar issues within other network equipment, as this class of vulnerability commonly affects embedded web servers in networking equipment. The vulnerability demonstrates the importance of input validation in embedded systems and highlights the need for security-by-design principles in network device development to prevent similar issues from occurring in future deployments.