1. EXECUTIVE SUMMARY
- CVSS v3 8.0
- ATTENTION: Exploitable remotely/low attack complexity/public exploits are available/known public exploitation
- Vendor: QNAP
- Equipment: VioStor NVR
- Vulnerability: OS Command Injection
2. RISK EVALUATION
Successful exploitation of this vulnerability could allow an attacker to achieve remote code execution by exploiting NTP settings.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following versions of QNAP VioStor NVR, are affected:
- VioStor NVR QVR firmware: All versions prior to 4.x
3.2 Vulnerability Overview
3.2.1 IMPROPER NEUTRALIZATION OF SPECIAL ELEMENTS USED IN AN OS COMMAND (‘OS COMMAND INJECTION’) CWE-78
QNAP VioStor NVR versions prior to QVR Firmware 4.x are vulnerable to an OS command injection vulnerability that may allow an attacker to modify NTP settings in the device. This could result in remote code execution.
CVE-2023-47565 has been assigned to this vulnerability. A CVSS v3.1 base score of 8.0 has been calculated; the CVSS vector string is (AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
3.3 BACKGROUND
- CRITICAL INFRASTRUCTURE SECTORS: Commercial Facilities
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: Taiwan
3.4 RESEARCHER
Chad Seaman and Larry Cashdollar of Akamai Technologies reported this vulnerability to CISA.
4. MITIGATIONS
QNAP has provided that users should download and apply the latest QVR Firmware.
QNAP has stated that QVR Firmware 5.x and 4.x are both end of life.
For more information, see QNAP’s security advisory.
For more information, contact QNAP Support.
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability, such as:
- Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
- Locate control system networks and remote devices behind firewalls and isolating them from business networks.
- When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices.
CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.
CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.
CISA has received reports of this vulnerability being actively exploited.
This advisory contains a vulnerability that has an associated “Known Exploited Vulnerabilities” (KEV) entry. Refer to the following link to view the KEV entry: Known Exploited Vulnerabilities Catalog | CISA
5. UPDATE HISTORY
- December 21, 2023: Initial Publication