CVE-2019-20666 in RBR50
Summary
by MITRE
Certain NETGEAR devices are affected by stored XSS. This affects RBR50 before 2.3.5.30, RBS50 before 2.3.5.30, and RBK50 before 2.3.5.30.
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Analysis
by VulDB Data Team • 05/26/2024
The vulnerability identified as CVE-2019-20666 represents a critical stored cross-site scripting flaw affecting several NETGEAR router models including the RBR50 RBS50 and RBK50 series. This vulnerability resides in the web-based management interface of these networking devices, creating a persistent security risk that can be exploited by remote attackers to execute malicious scripts within the context of authenticated sessions. The affected firmware versions prior to 2.3.5.30 demonstrate a failure in proper input validation and output encoding mechanisms within the device's user interface components.
The technical implementation of this stored XSS vulnerability occurs when user-supplied input is not adequately sanitized before being stored and subsequently rendered in the web interface. Attackers can exploit this weakness by injecting malicious JavaScript code through input fields or parameters that are then persisted within the device's configuration storage. When other users or administrators access the affected management interface, the malicious script executes in their browser context, potentially leading to session hijacking, credential theft, or further exploitation of the compromised device. This vulnerability operates at the application layer and directly impacts the integrity of the web-based administration interface.
The operational impact of CVE-2019-20666 extends beyond simple script execution as it provides attackers with a persistent foothold within network infrastructure. Once exploited, the vulnerability allows attackers to manipulate network configurations, access sensitive administrative functions, and potentially establish backdoors for continued access. The stored nature of this vulnerability means that the malicious payload remains active even after the initial exploitation, creating a long-term threat vector that persists across device reboots and configuration changes. Network administrators face significant challenges in detecting and mitigating this threat as the malicious code is embedded within legitimate device operations.
Security practitioners should implement immediate mitigations including firmware updates to versions 2.3.5.30 or later which address the input validation deficiencies. Network segmentation and access control measures should be strengthened to limit administrative access to these devices, while monitoring systems should be configured to detect unusual patterns in device configuration changes or web interface access. The vulnerability aligns with CWE-79 which categorizes cross-site scripting flaws, and represents a significant concern under the ATT&CK framework's credential access and persistence techniques. Organizations should conduct comprehensive vulnerability assessments to identify all affected devices and ensure proper patch management protocols are in place to prevent similar issues in other network infrastructure components.