CVE-2021-45606 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 1.0.1.70, R7000 before 1.0.11.126, R7900 before 1.0.4.46, R7900P before 1.4.2.84, R7960P before 1.4.2.84, R8000 before 1.0.4.74, R8000P before 1.4.2.84, RAX200 before 1.0.4.120, RS400 before 1.5.1.80, R6400v2 before 1.0.4.118, R7000P before 1.3.3.140, RAX80 before 1.0.4.120, R6700v3 before 1.0.4.118, R6900P before 1.3.3.140, and RAX75 before 1.0.4.120.
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Analysis
by VulDB Data Team • 12/28/2021
This vulnerability represents a critical stack-based buffer overflow condition that affects multiple NETGEAR router models, specifically targeting devices running firmware versions prior to the listed secure releases. The flaw exists within the web management interface of these networking devices, creating a path for authenticated attackers to execute arbitrary code through crafted input parameters. The vulnerability stems from improper bounds checking in the handling of user-supplied data within the device's web server component, allowing an attacker with valid credentials to overwrite adjacent stack memory locations. This type of vulnerability falls under CWE-121 Stack-based Buffer Overflow, which is classified as a serious weakness in software security design where data is written beyond the bounds of a fixed-length buffer allocated on the stack. The affected devices include popular router models such as the R6400, R7000, R7900, and various other variants across multiple product lines, indicating a widespread issue affecting the manufacturer's product portfolio.
The operational impact of this vulnerability is severe as it enables authenticated remote code execution, which could allow an attacker who has gained access to the device's administrative interface to escalate privileges and potentially gain full control over the affected router. The stack-based buffer overflow allows for memory corruption that can be leveraged to execute malicious code with the privileges of the web server process, typically running as root or with elevated system permissions. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under T1059 Command and Scripting Interpreter and T1068 Exploitation for Privilege Escalation, where attackers can use such vulnerabilities to establish persistent access to network infrastructure. The affected firmware versions suggest that this was a long-standing issue that required multiple updates across different product generations, indicating that the vulnerability was present in the codebase for an extended period.
Mitigation strategies for this vulnerability require immediate firmware updates from NETGEAR to address the buffer overflow conditions in the web management interface. Organizations should implement network segmentation to limit access to administrative interfaces and ensure that only authorized personnel have administrative credentials. Network monitoring should be enhanced to detect unusual traffic patterns that might indicate exploitation attempts, particularly focusing on web requests that contain oversized parameters or malformed input data. Device administrators should also enforce strong authentication mechanisms including multi-factor authentication and regular credential rotation to reduce the risk of unauthorized access. Additionally, implementing network access controls such as firewalls that restrict access to administrative ports from trusted networks only can significantly reduce the attack surface. Security teams should conduct regular vulnerability assessments of network infrastructure to identify similar issues in other network devices and ensure that all firmware is kept current with the latest security patches. The vulnerability demonstrates the importance of proper input validation and memory management practices in embedded systems, as highlighted by industry security standards that emphasize defensive programming techniques to prevent such buffer overflow conditions.