CVE-2021-44373 in RLC-410W
Summary
by MITRE • 01/29/2022
A denial of service vulnerability exists in the cgiserver.cgi JSON command parser functionality of reolink RLC-410W v3.0.0.136_20121102. A specially-crafted HTTP request can lead to a reboot. SetAutoFocus param is not object. An attacker can send an HTTP request to trigger this vulnerability.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 02/02/2022
The CVE-2021-44373 vulnerability represents a critical denial of service condition affecting the reolink RLC-410W security camera device running firmware version 3.0.0.136_20121102. This vulnerability specifically targets the cgiserver.cgi JSON command parser functionality, which serves as the primary interface for remote device management and configuration. The flaw manifests when the system processes HTTP requests containing malformed JSON data, particularly in the SetAutoFocus parameter handling. The vulnerability operates at the application layer and demonstrates poor input validation practices that allow attackers to manipulate the device's operational state through crafted network traffic.
The technical implementation of this vulnerability stems from insufficient parameter validation within the JSON parser component of the device's web server. When an attacker submits an HTTP request containing a malformed SetAutoFocus parameter that is not properly structured as a JSON object, the parser fails to handle this unexpected input gracefully. Instead of rejecting the malformed request or processing it safely, the system enters a state where it reboots the device as a result of the unhandled exception. This behavior aligns with CWE-248, which addresses "Uncaught Exception" conditions in software systems, and represents a classic example of how improper error handling can lead to system instability and denial of service conditions.
The operational impact of this vulnerability extends beyond simple service disruption, as it provides an attacker with a reliable method to continuously reboot the security camera device. This can effectively disable the device's monitoring capabilities and potentially create a window of opportunity for more sophisticated attacks. The vulnerability is particularly concerning in security contexts where continuous monitoring is critical, as it can be exploited to maintain persistent access to the device or to create a denial of service for legitimate users. The attack vector requires only the ability to send HTTP requests to the device, making it accessible to attackers with minimal technical expertise. This aligns with ATT&CK technique T1499.004, which covers "Endpoint Denial of Service" through manipulation of device reboot functionality.
Mitigation strategies for this vulnerability should include immediate firmware updates from the vendor to address the JSON parsing error and implement proper input validation for all parameters. Network segmentation and access controls should be implemented to limit who can send HTTP requests to the device, while monitoring systems should be deployed to detect unusual reboot patterns. The device should also be configured to disable unnecessary web services and ensure that only authorized personnel have access to the management interface. Additionally, network administrators should consider implementing intrusion detection systems to monitor for the specific patterns of HTTP requests that trigger this vulnerability, as well as maintaining regular backups of device configurations to quickly restore functionality after potential exploitation.