CVE-2021-44415 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. ModifyUser param is not object. An attacker can send an HTTP request to trigger this vulnerability.
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Analysis
by VulDB Data Team • 02/02/2022
This vulnerability resides in the cgiserver.cgi component of reolink RLC-410W security camera firmware version 3.0.0.136_20121102, representing a critical denial of service flaw that can be exploited to remotely reboot the device. The vulnerability specifically manifests within the JSON command parser functionality where the system fails to properly validate the ModifyUser parameter, which should be an object but is instead being processed as a malformed input. This improper handling occurs during HTTP request processing when the device receives a specially crafted payload designed to exploit the lack of input sanitization. The flaw stems from inadequate parameter validation and insufficient error handling within the JSON parsing mechanism, allowing an attacker to craft malicious requests that cause the system to crash and subsequently reboot.
The technical implementation of this vulnerability aligns with CWE-20, which describes improper input validation, and CWE-122, which covers heap-based buffer overflow conditions. The attack vector requires only a simple HTTP request to be sent to the affected device, making it particularly dangerous as it can be exploited remotely without requiring physical access or authentication credentials. The device's JSON parser does not properly validate that the ModifyUser parameter conforms to expected object structure, allowing malformed data to be processed and ultimately causing a system crash. This behavior demonstrates a classic example of insufficient input sanitization where the system assumes valid data structure without proper validation checks.
From an operational perspective, this vulnerability presents a significant risk to security infrastructure deployments where these cameras are used for surveillance and monitoring. The remote reboot capability can be leveraged to create persistent denial of service conditions, effectively removing critical security monitoring capabilities from the network. The impact extends beyond simple service disruption as it can be used to mask other attacks or create windows of opportunity for additional exploitation. Security operations teams may experience false positives in their monitoring systems due to unexpected reboots, and the vulnerability can be exploited as part of larger attack campaigns targeting network infrastructure. The low complexity attack requirement means that even amateur threat actors can potentially exploit this vulnerability to compromise security operations.
Mitigation strategies should include immediate firmware updates from reolink to address the underlying parsing flaw, network segmentation to limit access to affected devices, and implementation of intrusion detection systems to monitor for suspicious HTTP request patterns. The vulnerability also highlights the importance of proper input validation and parameter checking in web application development, aligning with ATT&CK technique T1499.004 for network denial of service. Organizations should implement access controls to restrict HTTP request capabilities to trusted sources only and consider deploying network-based firewalls to filter malformed requests. Additionally, regular security assessments of embedded devices should include verification of input validation mechanisms and proper error handling to prevent similar vulnerabilities from being present in other components of the security infrastructure.