CVE-2026-11732 in CAX30
Summary
by MITRE • 10/13/2026
An insufficient input validation vulnerability in the website blocking feature (Block Sites) of the listed NETGEAR router models allows a network-adjacent attacker having network access (such as WiFi credentials) to run unauthorized commands on the router. This vulnerability could affect the confidentiality, integrity, and availability of the affected router. It applies only when the Block Sites feature is turned on.
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Analysis
by VulDB Data Team • 10/16/2026
The identified security flaw resides within the website blocking functionality, specifically known as Block Sites, of various NETGEAR router models. This component is designed to restrict user access to specific domains or IP addresses by filtering network traffic based on a predefined list. The core technical deficiency lies in insufficient input validation when processing entries added to this blocklist. Rather than strictly sanitizing and validating the format of domain names or URLs provided by the administrator, the system fails to adequately check for maliciously crafted inputs that could be interpreted as executable commands. This lack of rigorous boundary checking creates a pathway for command injection attacks, where an attacker can manipulate the input fields to inject shell commands into the router's underlying operating system processes.
The exploitation vector requires network adjacency, meaning the attacker must have legitimate access to the local area network managed by the affected device. In practical terms, this typically involves possessing valid Wi-Fi credentials or being connected via a wired Ethernet link within the same subnet. The vulnerability is conditional and only active when the Block Sites feature is enabled on the router firmware. Once an authenticated user with appropriate privileges adds a maliciously formatted entry to the block list, the router's internal processing logic executes these commands without proper isolation or validation. This allows the attacker to achieve arbitrary code execution within the context of the router’s operating system, which often runs with elevated privileges such as root access.
The operational impact of this vulnerability is severe and multifaceted, affecting all three pillars of information security: confidentiality, integrity, and availability. By gaining command-line access, an attacker can exfiltrate sensitive network configuration data, including Wi-Fi passwords, DNS settings, and potentially credentials stored in the router’s memory or flash storage, thereby compromising confidentiality. The integrity of the device is undermined as the attacker can modify system files, alter firewall rules to bypass security controls, install persistent backdoors for future access, or redirect traffic through malicious proxies. Furthermore, availability is threatened because the attacker could crash critical network services, disrupt internet connectivity for all connected devices, or use the router as a pivot point for further attacks against other internal assets.
From a classification perspective, this vulnerability aligns with CWE-94 Improper Control of Generation of Code (Command Injection), specifically where user input is directly incorporated into system commands without adequate sanitization. In terms of adversary tactics and techniques, it maps to ATT&CK technique T1053 Scheduled Task/Job, as the attacker may leverage scheduled tasks or cron jobs for persistence, and potentially T1218 System Binary Proxy Execution if they utilize legitimate system utilities to execute malicious payloads. The attack also relates to MITRE ATT&CK tactic TA0001 Initial Access via valid credentials, given that network adjacency and authentication are prerequisites.
Mitigation strategies must address both immediate remediation and long-term security posture improvements. The primary defense is the application of firmware updates provided by NETGEAR that patch this specific input validation flaw in the Block Sites feature. Administrators should ensure all affected devices are updated to the latest stable release as soon as possible. In environments where immediate patching is not feasible, temporary mitigations include disabling the Block Sites feature entirely if it is not strictly required for network policy enforcement. Additionally, implementing strict access controls on the router’s administrative interface and ensuring that only trusted users have Wi-Fi credentials can reduce the attack surface. Network segmentation should also be considered to limit lateral movement in case of a compromise, isolating critical assets from general user networks where such vulnerabilities might exist.