CVE-2019-20753 in DGN2200v1
Summary
by MITRE
Certain NETGEAR devices are affected by a stack-based buffer overflow by an unauthenticated attacker. This affects DGN2200v1 before 1.0.0.58, D8500 before 1.0.3.42, D7000v2 before 1.0.0.51, D6400 before 1.0.0.78, D6220 before 1.0.0.44, JNDR3000 before 1.0.0.24, R8000 before 1.0.4.18, R8500 before 1.0.2.122, R8300 before 1.0.2.122, R7900 before 1.0.2.16, R7000P before 1.3.2.34, R7300DST before 1.0.0.68, R7100LG before 1.0.0.46, R6900P before 1.3.2.34, R7000 before 1.0.9.28, R6900 before 1.0.1.46, R6700 before 1.0.1.46, R6400v2 before 1.0.2.56, R6400 before 1.0.1.42, R6300v2 before 1.0.4.28, R6250 before 1.0.4.26, WNDR3400v3 before 1.0.1.22, WNDR4500v2 before 1.0.0.72, and WNR3500Lv2 before 1.2.0.50.
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Analysis
by VulDB Data Team • 05/31/2024
This vulnerability represents a critical stack-based buffer overflow flaw in NETGEAR router firmware that enables unauthenticated remote code execution. The issue stems from improper input validation within the device's web interface handling routines, where attacker-controlled data can overwrite adjacent memory locations on the stack. This flaw affects a broad range of NETGEAR router models spanning multiple product lines including the DGN2200v1, D8500, R8000, and numerous other variants. The vulnerability exists in firmware versions prior to the specified patches, indicating that manufacturers released updates to address this specific memory corruption issue. According to CWE-121, this corresponds to a stack-based buffer overflow where insufficient bounds checking allows data to overwrite stack memory, potentially leading to arbitrary code execution.
The operational impact of this vulnerability is severe as it allows any remote attacker to exploit the flaw without requiring authentication credentials. This creates a significant risk for network infrastructure since attackers can gain complete control over affected devices, potentially leading to man-in-the-middle attacks, data exfiltration, or use of the compromised device as a pivot point for further network penetration. The vulnerability's exploitability is enhanced by the fact that it requires no prior authentication, making it particularly dangerous in enterprise and residential network environments. Attackers can leverage this weakness to redirect traffic, modify network settings, or establish persistent backdoors within the network infrastructure.
Network security professionals should immediately implement mitigation strategies including firmware updates from NETGEAR, network segmentation to isolate affected devices, and monitoring for suspicious network activity. The ATT&CK framework categorizes this vulnerability under T1210 - Exploitation of Remote Services, where attackers leverage unauthenticated access to gain system-level privileges. Organizations should also consider implementing intrusion detection systems to monitor for exploitation attempts and establish network access controls to limit exposure. The vulnerability's widespread impact across multiple device models suggests that organizations with extensive NETGEAR deployments should conduct comprehensive inventory assessments to identify all potentially affected devices and prioritize remediation efforts accordingly.
The technical nature of this buffer overflow indicates that attackers can manipulate input parameters through web interface requests to cause memory corruption. This typically involves crafting malicious HTTP requests that exceed buffer boundaries, potentially overwriting return addresses or function pointers on the stack. The vulnerability demonstrates poor software development practices regarding input validation and memory management, which aligns with common security weaknesses identified in industry standards. Organizations should also consider implementing network-level protections such as firewall rules to restrict access to router management interfaces and establish secure remote access protocols to minimize exposure windows. Regular security assessments and vulnerability scanning should be conducted to identify similar issues in other network equipment and ensure comprehensive network security posture.