CVE-2021-45552 in D7800
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D7800 before 1.0.1.58, R7500v2 before 1.0.3.48, R7800 before 1.0.2.68, R8900 before 1.0.5.2, R9000 before 1.0.5.2, RAX120 before 1.0.1.108, and XR700 before 1.0.1.20.
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Analysis
by VulDB Data Team • 12/28/2021
This vulnerability represents a critical command injection flaw in NETGEAR networking equipment that allows authenticated attackers to execute arbitrary commands on affected devices. The vulnerability stems from insufficient input validation and sanitization within the web interface authentication system, enabling an attacker who has already gained access to the device through legitimate credentials to escalate their privileges and execute malicious commands with root-level privileges. The affected models span multiple product lines including the D7800, R7500v2, R7800, R8900, R9000, RAX120, and XR700 series, indicating a widespread issue across NETGEAR's router and modem product portfolio. This type of vulnerability falls under CWE-77 which specifically addresses command injection flaws in software systems. The security implications are severe as command injection attacks can allow attackers to gain complete control over network infrastructure, potentially leading to man-in-the-middle attacks, data exfiltration, or the establishment of persistent backdoors within corporate or residential networks.
The operational impact of this vulnerability extends beyond simple privilege escalation as it enables attackers to manipulate network configurations, redirect traffic, or establish unauthorized access points. When an attacker successfully exploits this vulnerability, they can execute commands that modify firewall rules, change DNS settings, or even install malicious firmware updates. The affected firmware versions indicate that this is not a recent issue but has persisted across multiple generations of NETGEAR devices, suggesting inadequate security testing during development cycles. The vulnerability is particularly concerning because it requires only authenticated access, meaning that an attacker who has already compromised legitimate user credentials can leverage this flaw to gain full administrative control. This aligns with ATT&CK technique T1078 which covers legitimate credentials and T1059 which covers command and scripting interpreters, making this vulnerability a prime example of how authenticated access can be escalated to full system compromise. Network administrators should be aware that even if their network appears secure from external attacks, internal authenticated users who are compromised can provide attackers with a path to complete network takeover.
Mitigation strategies for this vulnerability must include immediate firmware updates from NETGEAR to address the command injection flaw in all affected models. Organizations should implement network segmentation to limit the impact of potential compromise and ensure that administrative access is restricted to authorized personnel only. Regular security audits of network infrastructure should include verification of device firmware versions and patch management processes. Additional defensive measures include monitoring for unusual network behavior, implementing strong authentication mechanisms, and maintaining detailed logs of administrative activities. The vulnerability demonstrates the importance of secure coding practices and input validation, particularly in web-based management interfaces where user input is processed and executed. Organizations should also consider implementing network access control lists and intrusion detection systems to identify potential exploitation attempts. Given the nature of command injection vulnerabilities, it is crucial to follow the principle of least privilege and ensure that administrative interfaces are protected through multi-factor authentication and secure network design principles. The affected devices should be isolated from critical network segments until patches are applied and security configurations are verified. This vulnerability serves as a reminder of the critical importance of maintaining up-to-date firmware and the potential consequences of insufficient security testing in networking equipment that controls core network infrastructure.