ZyXEL GS1900 Access Control Error Vulnerability

Zyxel ZyXEL GS1900 is a managed switch from Zyxel, Taiwan, China. An access control error vulnerability exists in several Zyxel products. The vulnerability stems from the product’s TFTP client not adding permission control to the function that can execute system commands. An attacker can execute arbitrary OS commands through this vulnerability after login.