Rewriting History: Changing the Archived Web from the Present.

The Internet Archive's Wayback Machine is the largest modern web archive, preserving web content since 1996. We discover and analyze several vulnerabilities in how the Wayback Machine archives data, and then leverage these vulnerabilities to create what are to our knowledge the first attacks against a user's view of the archived web. Our vulnerabilities are enabled by the unique interaction between the Wayback Machine's archives, other websites, and a user's browser, and attackers do not need to compromise the archives in order to compromise users' views of a stored page. We demonstrate the effectiveness of our attacks through proof-of-concept implementations. Then, we conduct a measurement study to quantify the prevalence of vulnerabilities in the archive. Finally, we explore defenses which might be deployed by archives, website publishers, and the users of archives, and present the prototype of a defense for clients of the Wayback Machine, ArchiveWatcher.