CVE-2017-14263 in NVR
Summary
by MITRE
Honeywell NVR devices allow remote attackers to create a user account in the admin group by leveraging access to a guest account to obtain a session ID, and then sending that session ID in a userManager.addUser request to the /RPC2 URI. The attacker can login to the device with that new user account to fully control the device.
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Analysis
by VulDB Data Team • 11/14/2019
This vulnerability in Honeywell NVR devices represents a critical authentication bypass flaw that allows remote attackers to escalate privileges from guest to administrator level. The vulnerability stems from improper session management and insufficient access controls within the device's RPC interface, specifically the /RPC2 URI endpoint. Attackers can exploit this by first obtaining a valid session ID through a guest account, then leveraging that session ID to make unauthorized userManager.addUser requests that create new administrator accounts. This type of vulnerability falls under CWE-287 which addresses improper authentication issues and aligns with ATT&CK technique T1190 for exploiting vulnerabilities in remote services.
The technical implementation of this flaw involves the device's failure to validate that the session ID being used for administrative operations actually corresponds to an authenticated administrator account. Instead, the system accepts any valid session ID and permits the creation of new user accounts with elevated privileges. This weakness exists because the authentication check occurs at the session level rather than at the individual request level for administrative functions. The RPC2 interface lacks proper authorization verification, allowing any authenticated user to perform administrative actions through the userManager.addUser endpoint, which violates fundamental security principles of least privilege and proper access control enforcement.
The operational impact of this vulnerability is severe as it provides attackers with complete administrative control over the NVR device, enabling them to view, modify, or delete all recorded video footage, change system configurations, add or remove users, and potentially access other network resources connected to the same network segment. This represents a significant risk for organizations relying on these devices for security monitoring, as it allows attackers to completely compromise the integrity and availability of their surveillance systems. The vulnerability is particularly dangerous because it requires minimal privileges to exploit, making it accessible to attackers who may only have guest-level access to the system.
Mitigation strategies should include immediate firmware updates from Honeywell to address the session management flaw, implementation of network segmentation to isolate NVR devices from critical systems, and enforcement of strong access controls including multi-factor authentication. Organizations should also consider disabling unnecessary RPC interfaces, implementing network access controls to restrict access to the /RPC2 URI, and conducting regular security audits of networked devices. The vulnerability demonstrates the importance of proper session validation and authorization checks in web applications and network services, aligning with security frameworks that emphasize the need for robust authentication mechanisms and principle of least privilege implementation. Additionally, network monitoring should be enhanced to detect unusual administrative account creation patterns and unauthorized access attempts to the RPC2 interface.