CVE-2026-71931 [HIGH] – Multiple DrayTek VigorSwitch models contain a command injection vulnerability in the tftp_

Multiple DrayTek VigorSwitch models contain a command injection vulnerability in the tftp_upgrade function. The vulnerability is caused by insufficient filtering before the filename field is concatenated into a command. A remote attacker can trigger this vulnerability via crafted input to execute arbitrary commands with root privileges. Exploitation requires valid administrative credentials for the device’s web management interface.