CVE-2022-27982 in RG-NBR-E Enterprise Gateway
Summary
by MITRE • 05/02/2022
RG-NBR-E Enterprise Gateway RG-NBR2100G-E was discovered to contain a remote code execution (RCE) vulnerability via the fileName parameter at /guest_auth/cfg/upLoadCfg.php.
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Analysis
by VulDB Data Team • 05/04/2022
The CVE-2022-27982 vulnerability represents a critical remote code execution flaw in the RG-NBR2100G-E Enterprise Gateway device manufactured by RG-NBR-E. This vulnerability exists within the web interface of the device and specifically targets the file upload functionality located at the /guest_auth/cfg/upLoadCfg.php endpoint. The vulnerability stems from insufficient input validation and sanitization of the fileName parameter, which allows authenticated attackers to upload malicious files to the device's file system. This flaw enables adversaries to execute arbitrary code on the affected system with the privileges of the web application, potentially leading to complete system compromise and unauthorized access to network resources.
The technical exploitation of this vulnerability follows a well-established pattern that aligns with CWE-434, which describes insecure file upload vulnerabilities where applications allow users to upload files without proper validation. The attacker must first authenticate to the device, typically through legitimate administrative credentials, before exploiting the upload functionality. The fileName parameter does not properly validate file extensions or content, allowing malicious actors to upload scripts or binaries that can be executed by the web server. This vulnerability directly maps to the ATT&CK technique T1566.001 for initial access through malicious file uploads and T1059 for command and scripting interpreter usage.
The operational impact of CVE-2022-27982 extends beyond simple remote code execution, as it provides attackers with a persistent foothold within enterprise networks. Once exploited, adversaries can establish backdoors, escalate privileges, and use the compromised device as a pivot point for further attacks against other network segments. The RG-NBR2100G-E gateway serves as a critical network infrastructure component, making this vulnerability particularly dangerous for organizations relying on it for network access control and guest authentication services. The device's role in managing network access makes it an attractive target for attackers seeking to maintain long-term access to corporate networks while evading detection mechanisms.
Organizations should implement immediate mitigations including network segmentation to isolate affected devices, disabling unnecessary file upload functionality where possible, and implementing robust input validation controls. The device firmware should be updated to the latest version provided by the vendor, as this vulnerability is likely addressed through proper parameter validation and access controls. Network monitoring should be enhanced to detect unusual file upload activities and potential exploitation attempts. Additionally, implementing web application firewalls and security controls at the network perimeter can help prevent exploitation attempts. Regular vulnerability assessments and penetration testing should be conducted to identify similar insecure file handling practices in other network infrastructure components. The vulnerability highlights the importance of following secure coding practices and input validation principles as outlined in OWASP Top Ten and NIST cybersecurity guidelines to prevent similar issues in enterprise network devices.