CVE-2018-21118 in XR500
Summary
by MITRE
NETGEAR XR500 devices before 2.3.2.32 are affected by authentication bypass.
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Analysis
by VulDB Data Team • 06/01/2024
The NETGEAR XR500 router series represents a significant networking solution designed for enterprise and small office environments, incorporating advanced wireless capabilities and robust security features. However, a critical authentication bypass vulnerability has been identified in firmware versions prior to 2.3.2.32, fundamentally compromising the device's security posture. This vulnerability stems from improper handling of authentication mechanisms within the device's web interface and administrative access controls, creating a pathway for unauthorized users to gain administrative privileges without proper credentials.
The technical flaw manifests through a weakness in the authentication flow where the system fails to properly validate user credentials during the login process. Attackers can exploit this by manipulating the authentication sequence to bypass the standard login requirements entirely. This issue typically occurs due to insufficient input validation, improper session management, or flawed access control checks within the web application layer of the router's firmware. The vulnerability allows remote attackers to access the administrative interface and execute privileged operations, effectively compromising the entire network infrastructure managed by the device.
The operational impact of this authentication bypass vulnerability extends far beyond simple unauthorized access, as it enables complete compromise of the affected network devices. An attacker with access to the administrative interface can modify network configurations, implement malicious routing rules, disable security features, and potentially establish backdoors for persistent access. This vulnerability particularly affects enterprise networks where the XR500 devices serve as primary gateways, as it could lead to complete network infiltration, data exfiltration, and disruption of critical business operations. The remote nature of the exploit means that attackers do not require physical access to the device, making the attack surface significantly broader.
Network security professionals should prioritize immediate firmware updates to version 2.3.2.32 or later, which contain the necessary patches addressing the authentication bypass vulnerability. Additionally, network segmentation strategies should be implemented to limit the potential impact of such compromises, ensuring that even if one device is compromised, the broader network remains protected. Organizations should conduct thorough network audits to identify all affected devices and implement monitoring solutions to detect suspicious authentication attempts. The vulnerability aligns with CWE-287, which addresses improper authentication issues, and represents a significant concern under the ATT&CK framework's privilege escalation tactics, specifically targeting the T1078 technique for valid accounts usage.
Security measures should include implementing strong network access controls, enabling multi-factor authentication where possible, and establishing regular vulnerability assessment procedures. Device administrators should also consider disabling unnecessary remote management features and implementing network intrusion detection systems to monitor for exploitation attempts. The patching process must be carefully coordinated to avoid service disruptions while ensuring comprehensive protection against this and similar vulnerabilities. Organizations should also review their incident response procedures to ensure readiness for potential exploitation of this authentication bypass vulnerability.