Research shows that some ISPs have started injecting advertisements into web pages requested by their end users. As a result, we set out to measure how often web pages are changed after leaving the server and before arriving in the user's browser.
At a high level, we found that approximately 1% of users receive pages that have been changed "in-flight." Most of these changes are caused by software that users install on their computer (such as personal firewalls or ad blockers), but many are caused by agents in the network, such as ISPs and enterprise firewalls. Worse, we found that many of the products that users install introduce bugs or security vulnerabilities into the web pages they request.
Web Tripwire Security Software is one of the many software programs and tools created at the University of Washington available through our Express Licensing Program. These agreements have standard terms and conditions that allow for rapid licensing by companies, organizations, or individuals.