CVE-2023-37794 in FBM-291W
Summary
by MITRE • 07/15/2023
WAYOS FBM-291W 19.09.11V was discovered to contain a command injection vulnerability via the component /upgrade_filter.asp.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 01/18/2026
The vulnerability identified as CVE-2023-37794 affects the WAYOS FBM-291W router model running firmware version 19.09.11V. This device operates within the consumer and small office networking space, providing wireless connectivity and network management capabilities to end users. The vulnerability manifests through the /upgrade_filter.asp component which processes user input without adequate sanitization or validation. This particular web interface component appears to handle firmware upgrade filtering operations and likely processes parameters that control how upgrade files are validated or processed. The device's web management interface presents an attack surface that exposes this command injection flaw to potential adversaries who can manipulate the upgrade process through crafted input parameters.
The technical flaw represents a command injection vulnerability that falls under CWE-77, which specifically addresses improper neutralization of special elements used in commands. This weakness occurs when user-supplied data is directly incorporated into system commands without proper input validation or sanitization. The /upgrade_filter.asp component likely constructs system commands by concatenating user-provided parameters with shell commands, creating an environment where malicious input can execute arbitrary commands with the privileges of the web application process. The vulnerability is particularly concerning because it targets a firmware upgrade component, which typically operates with elevated privileges and can potentially allow attackers to modify the device's core functionality or install malicious code.
The operational impact of this vulnerability extends beyond simple remote code execution, as it can enable attackers to compromise the entire network infrastructure controlled by the affected router. An attacker who successfully exploits this vulnerability can gain persistent access to the device and potentially use it as a pivot point to attack other devices on the local network. The compromised router could be used to redirect traffic, monitor communications, or serve as a command and control node for further attacks. Additionally, since this vulnerability affects a firmware upgrade component, it could allow attackers to install malicious firmware versions that maintain persistence even after device reboots or factory resets. This makes the attack surface particularly dangerous for enterprise environments where these devices might be deployed without proper security monitoring or management.
Mitigation strategies for CVE-2023-37794 should prioritize immediate firmware updates from WAYOS if available, as this represents the most direct solution to address the underlying vulnerability. Network administrators should implement network segmentation to limit the potential impact of a compromised device and deploy intrusion detection systems to monitor for suspicious traffic patterns that might indicate exploitation attempts. The principle of least privilege should be applied by ensuring that the web interface components have minimal necessary permissions and that input validation is implemented at multiple layers. Organizations should also consider disabling unnecessary web management interfaces when not actively required and implement network access controls to limit who can reach the affected device. From an ATT&CK framework perspective, this vulnerability maps to T1059.001 (Command and Scripting Interpreter: PowerShell) and T1021.001 (Remote Services: Remote Desktop Protocol) as attackers could leverage this to establish persistent access and execute commands on the network. Regular security assessments and vulnerability scanning should be implemented to identify similar weaknesses in other network infrastructure components.