CVE-2020-11773 in D7800
Summary
by MITRE
Certain NETGEAR devices are affected by stored XSS. This affects D7800 before 1.0.1.56, R7500v2 before 1.0.3.46, R7800 before 1.0.2.68, R8900 before 1.0.4.28, R9000 before 1.0.4.28, RAX120 before 1.0.0.78, XR500 before 2.3.2.56, and XR700 before 1.0.1.10.
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Analysis
by VulDB Data Team • 05/27/2024
The vulnerability identified as CVE-2020-11773 represents a critical stored cross-site scripting flaw affecting multiple NETGEAR router models, including the D7800, R7500v2, R7800, R8900, R9000, RAX120, XR500, and XR700 series. This vulnerability resides within the web-based management interfaces of these devices, creating a persistent security risk that can be exploited by attackers to execute malicious scripts in the context of authenticated users. The flaw stems from inadequate input validation and output encoding mechanisms within the device's web interface, allowing malicious payloads to be stored and subsequently executed when legitimate users access the affected management pages. This stored XSS vulnerability specifically impacts firmware versions prior to the mentioned patch levels, indicating that NETGEAR has acknowledged and addressed the issue in subsequent releases. The affected devices operate under the assumption that user inputs from web forms will be properly sanitized before being stored in the device's configuration or session management systems, but this sanitization process fails to adequately handle malicious script content.
The technical exploitation of this vulnerability requires an attacker to gain access to the device's web management interface, typically through legitimate authentication credentials, though in some cases the vulnerability may be exploitable without authentication depending on the specific device configuration. Once authenticated, the attacker can inject malicious JavaScript code into various input fields within the web interface, such as configuration parameters, user names, or device settings. This injected code is then stored persistently within the device's memory or configuration files and executed whenever the web interface is accessed by any user, including administrators. The stored nature of this vulnerability means that the malicious payload remains active even after the initial injection, creating a persistent threat that can be exploited repeatedly. The vulnerability aligns with CWE-79, which describes cross-site scripting flaws, and specifically manifests as a stored XSS variant where the malicious input is saved and later executed in the context of the victim's browser session. This weakness enables attackers to potentially steal session cookies, redirect users to malicious sites, or execute arbitrary commands on the device.
The operational impact of CVE-2020-11773 extends beyond simple script execution, as it provides attackers with a foothold for more sophisticated attacks within the network infrastructure. An attacker who successfully exploits this vulnerability could potentially escalate privileges, access sensitive configuration data, or use the compromised device as a pivot point for attacking other systems within the local network. The vulnerability affects the management plane of these devices, which means that successful exploitation could lead to complete compromise of the router's administrative functions. Network administrators who access the affected devices through web browsers become potential victims of the stored XSS attack, as their browser sessions could be hijacked or their credentials potentially harvested. The impact is particularly concerning given that these devices often serve as the primary gateway between internal networks and external internet access, making them prime targets for attackers seeking to establish persistent access or conduct man-in-the-middle attacks. The vulnerability also violates fundamental security principles outlined in the NIST Cybersecurity Framework, specifically addressing the protection of information systems and the prevention of unauthorized access to sensitive data.
Mitigation strategies for this vulnerability should focus on immediate firmware updates from NETGEAR, which address the root cause by implementing proper input validation and output encoding mechanisms. Organizations should prioritize updating all affected device models to their latest firmware versions, as these updates contain the necessary patches to prevent the storage and execution of malicious scripts. Network segmentation and access control measures should be implemented to limit the exposure of these devices to untrusted networks, reducing the attack surface for potential exploitation attempts. Additionally, network monitoring should be enhanced to detect unusual patterns in web traffic or device configuration changes that might indicate exploitation attempts. Security awareness training for network administrators should emphasize the importance of maintaining updated firmware and recognizing potential signs of compromise in network infrastructure devices. The vulnerability also highlights the importance of implementing secure coding practices and conducting regular security assessments of network equipment, particularly focusing on input validation and output encoding mechanisms. Organizations should consider implementing network-based intrusion detection systems to monitor for potential exploitation attempts targeting these specific device models, as the stored nature of the vulnerability means that once exploited, the malicious payload remains active until the device is properly patched or the configuration is manually cleared.