CVE-2021-20843: Ntt-West Biz Box NVR510 Firmware

Medium severity, CVSS 5.4. EPSS: 0.7% chance of exploitation in the next 30 days.

Cross-site script inclusion vulnerability in the Web GUI of RTX830 Rev.15.02.17 and earlier, NVR510 Rev.15.01.18 and earlier, NVR700W Rev.15.00.19 and earlier, and RTX1210 Rev.14.01.38 and earlier allows a remote authenticated attacker to alter the settings of the product via a specially crafted web page.

Affected products

• Ntt-West Biz Box NVR510 Firmware: before 15.01.18 (fixed in 15.01.18)
• Ntt-West Biz Box NVR700W Firmware: up to and including 15.00.19
• Ntt-West Biz Box RTX1210 Firmware: up to and including 14.01.38
• Ntt-West Biz Box RTX830 Firmware: up to and including 15.02.17
• Yamaha NVR510 Firmware: up to and including 15.01.18
• Yamaha NVR700W Firmware: up to and including 15.00.19
• Yamaha RTX1210 Firmware: up to and including 14.01.38
• Yamaha RTX830 Firmware: up to and including 15.02.17

Published 2021-11-24. Last modified 2026-06-17.