CVE-2021-45605 in R6400
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by a stack-based buffer overflow by an authenticated user. This affects R6400 before 1.0.1.68, R7000 before 1.0.11.116, R6900P before 1.3.3.140, R7000P before 1.3.3.140, R7900 before 1.0.4.38, RAX75 before 1.0.3.102, RAX80 before 1.0.3.102, and XR300 before 1.0.3.50.
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Analysis
by VulDB Data Team • 12/28/2021
This vulnerability represents a critical stack-based buffer overflow flaw that affects multiple NETGEAR router models, specifically targeting devices in the R6400, R7000, R6900P, R7000P, R7900, RAX75, RAX80, and XR300 series. The flaw occurs within the web management interface of these devices, where an authenticated user can exploit improper input validation to overwrite adjacent memory locations on the stack. This vulnerability falls under the Common Weakness Enumeration category CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to write beyond allocated buffer boundaries. The affected firmware versions demonstrate a pattern of inadequate memory management practices that persist across multiple device generations, indicating a systemic issue in the software development lifecycle of these networking products.
The technical exploitation of this vulnerability requires an authenticated user to send specially crafted input to the device's web interface, typically through HTTP requests that manipulate parameters within the device configuration or management functions. When the device processes these malformed inputs without proper boundary checking, the stack buffer overflow occurs, potentially allowing an attacker to overwrite return addresses, function pointers, or other critical stack data. This type of vulnerability aligns with ATT&CK technique T1210, which covers exploitation of remote services through buffer overflow attacks, and represents a significant security risk since the attack requires only authentication credentials rather than physical access or advanced exploitation capabilities. The vulnerability's impact is particularly concerning given that these devices serve as primary network gateways for residential and small office environments, making them attractive targets for attackers seeking persistent access to network infrastructure.
The operational consequences of this vulnerability extend beyond simple privilege escalation, as successful exploitation could enable attackers to execute arbitrary code on the affected devices, potentially leading to complete network compromise. An attacker who gains control of a router through this vulnerability could redirect network traffic, intercept communications, modify network settings, or establish persistent backdoors within the network infrastructure. The affected device families represent common consumer and small business networking equipment, making this vulnerability particularly dangerous due to the widespread deployment of these models. Organizations and individuals using these devices face significant risk of network infiltration, data exfiltration, and potential use as launching points for broader attacks against connected systems. The vulnerability affects firmware versions that were widely deployed in 2020 and early 2021, indicating that many installations may remain unpatched and vulnerable to exploitation.
Mitigation strategies for this vulnerability should prioritize immediate firmware updates from NETGEAR, as the vendor has released patches addressing the buffer overflow conditions in the affected device models. Network administrators should also implement network monitoring to detect unusual traffic patterns that might indicate exploitation attempts, particularly focusing on malformed HTTP requests targeting device management interfaces. Additional protective measures include restricting access to device management interfaces through network segmentation, implementing strong authentication mechanisms, and regularly auditing device configurations to ensure that unnecessary services remain disabled. Organizations should also consider network access control policies that limit administrative access to only trusted network segments and implement intrusion detection systems capable of identifying suspicious patterns associated with buffer overflow exploitation attempts. The vulnerability underscores the importance of maintaining up-to-date firmware across all network infrastructure devices and demonstrates the critical need for proper input validation and memory management practices in embedded systems development.