Content management systems, methods, and media using an application level firewall are provided. In accordance with some embodiments of the disclosed subject matter, the system for managing advertisement adjacencies comprises: a firewall component in an application layer comprising a processor and a memory, wherein the firewall component is configured to operate in an advertisement call stack of the application layer and wherein the processor is programmed to: receive an advertisement call for publishing an advertisement in an advertisement server on a web page, wherein a verification tag is inserted in the advertisement call that redirects the advertisement call to the firewall component prior to transmission to the advertisement server; determine whether the web page associated with the advertisement call contains objectionable content; and, in response to determining that the web page does not contain objectionable content, transmit the advertisement call to the advertisement server for publishing the advertisement on the web page.