A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker to execute arbitrary commands with root privileges on the underlying operating system of an affected device. The vulnerability is due to improper input sanitization. An attacker could exploit this vulnerability by uploading a crafted file to the web UI of an affected device. A successful exploit could allow the attacker to inject and execute arbitrary commands with root privileges on the device.
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-web-cmdinj3-44st5CcA