CVE-2018-21218 in D3600
Summary
by MITRE
Certain NETGEAR devices are affected by a buffer overflow by an unauthenticated attacker. This affects D3600 before 1.0.0.67, D6000 before 1.0.0.67, D6100 before 1.0.0.56, D7800 before 1.0.1.30, R6100 before 1.0.1.20, R7500 before 1.0.0.118, R7500v2 before 1.0.3.24, R9000 before 1.0.2.52, WNDR3700v4 before 1.0.2.96, WNDR4300 before 1.0.2.98, WNDR4300v2 before 1.0.0.50, WNDR4500v3 before 1.0.0.50, and WNR2000v5 before 1.0.0.62.
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Analysis
by VulDB Data Team • 06/04/2024
This vulnerability represents a critical buffer overflow condition affecting multiple NETGEAR router models that has significant implications for network security and device integrity. The flaw exists within the web interface handling of these devices, allowing unauthenticated attackers to exploit a memory corruption issue through specially crafted input parameters. The vulnerability stems from insufficient bounds checking in the processing of HTTP requests, particularly in the handling of user-supplied data that flows into fixed-size buffers without proper validation. This type of flaw falls under the common weakness enumeration CWE-121, which specifically addresses stack-based buffer overflow conditions, and is classified as a remote code execution vulnerability that can be exploited without requiring any authentication credentials.
The operational impact of this vulnerability extends beyond simple device compromise, as it enables attackers to gain arbitrary code execution capabilities on affected devices. When exploited, the buffer overflow allows malicious actors to inject and execute arbitrary code within the router's memory space, potentially leading to complete device takeover. This compromise can result in persistent backdoor access, DNS hijacking, traffic interception, and the ability to redirect network traffic through malicious endpoints. The vulnerability affects a wide range of NETGEAR router models across different product lines, including both consumer and business-grade devices, making it particularly concerning from a scalability perspective. According to ATT&CK framework, this vulnerability maps to T1059.007 for command and scripting interpreter and T1566.001 for spearphishing via social engineering, as attackers could leverage this to establish persistent access and later conduct more sophisticated attacks.
Mitigation strategies for this vulnerability require immediate firmware updates from NETGEAR, as the company has released patches addressing the specific buffer overflow conditions in affected versions. Network administrators should prioritize updating all impacted devices to the latest firmware versions, which typically include input validation improvements and stack protection mechanisms. Additionally, implementing network segmentation and monitoring for unusual traffic patterns can help detect exploitation attempts, while disabling unnecessary services and ports on affected devices provides additional defensive layers. The vulnerability demonstrates the importance of secure coding practices and input validation, particularly in network infrastructure devices where persistent access can have cascading security implications. Organizations should also consider implementing network access controls and intrusion detection systems to monitor for exploitation attempts targeting these specific router models and their known vulnerable software versions.