Buffer overflow

An issue was discovered in NVR WebViewer on Hanwah Techwin SRN-472s 1.07_190502 devices, and other SRN-x devices before 2019-05-03. A system crash and reboot can be achieved by submitting a long username in excess of 117 characters. The username triggers a buffer overflow in the main process controlling operation of the DVR system, rendering services unavailable during the reboot operation. A repeated attack affects availability as long as the attacker has network access to the device.