D-Link DIR-600M devices allow XSS via the Hostname and Username fields in the Dynamic DNS Configuration page.
dir-600m_firmware
CVE-2020-13960
D-Link DSL 2730-U IN_1.10 and IN_1.11 and DIR-600M 3.04 devices have the domain.name string in the DNS resolver search path by default, which allows remote attackers to provide valid DNS responses (and also offer Internet services such as HTTP) for names that otherwise would have had an NXDOMAIN error, by registering a subdomain of the domain.name domain name.
CVE-2019-7736
D-Link DIR-600M C1 3.04 devices allow authentication bypass via a direct request to the wan.htm page. NOTE: this may overlap CVE-2019-13101.
CVE-2019-13101
An issue was discovered on D-Link DIR-600M 3.02, 3.03, 3.04, and 3.06 devices. wan.htm can be accessed directly without authentication, which can lead to disclosure of information about the WAN, and can also be leveraged by an attacker to modify the data fields of the page.