1. A method for performing security-focused web crawling by a server, comprising: identifying sensitive data on a first web page of a first user web browsing session, wherein identifying sensitive data comprises: selecting a first data item from one or more data items in the first web page; extracting a location of the first data item in the first web page; comparing the first data item with same data items on different webpage instances of the same web page browsed during a plurality of web browsing sessions, wherein each of the plurality of web browsing sessions is associated with a different user; determining whether the first data item changes across the plurality of different user web browsing sessions; identifying the first data item as non-sensitive data in response to determining that the first data item does not change across the plurality of web browsing sessions; determining whether the first data item correlates with a session identifier or a user input of each of the plurality of web browsing sessions in response to determining that the first data item changes across the plurality of web browsing sessions; and identifying the first data item as sensitive data having a dynamic pattern in response to determining the first data item correlates with a session identifier or a user input of each of the plurality of web browsing sessions; generating a first document object model (DOM) for the first web page that includes the sensitive data on the first web page and excludes at least some data items that are identified as non-sensitive; comparing one or more attributes of the sensitive data in the first DOM with the one or more attributes of sensitive data in a second DOM for a second web page instance of the same web page from a second user web browsing session of the different web browsing sessions; and determining whether the first web page is different from the second web page based on the comparison of the one or more attributes of the sensitive data in the first DOM and the second DOM being determined from the comparison as different.