HashClash

{{Short description|BOINC based volunteer computing project}}

{{Infobox software

| screenshot = Hashclash.png

| screenshot size = 300px

| operating system = cross-platform

| platform = BOINC

| website = {{URL|https://web.archive.org/web/20071016235617/http://boinc.banaan.org:80/hashclash/}}

}}

HashClash was a volunteer computing project running on the Berkeley Open Infrastructure for Network Computing (BOINC) software platform to find collisions in the MD5 hash algorithm.{{Cite web |date=2007-10-16 |title=HashClash |url=http://boinc.banaan.org:80/hashclash/ |access-date=2022-08-28 |archive-url=https://web.archive.org/web/20071016235617/http://boinc.banaan.org:80/hashclash/ |archive-date=2007-10-16 }} It was based at Department of Mathematics and Computer Science at the Eindhoven University of Technology, and Marc Stevens initiated the project as part of his master's degree thesis.

The project ended after Stevens defended his M.Sc. thesis in June 2007.Stevens's thesis "On Collisions for MD5" is [http://www.win.tue.nl/hashclash/On%20Collisions%20for%20MD5%20-%20M.M.J.%20Stevens.pdf available for download] {{Webarchive|url=https://web.archive.org/web/20170517115509/http://www.win.tue.nl/hashclash/On%20Collisions%20for%20MD5%20-%20M.M.J.%20Stevens.pdf |date=2017-05-17 }}. However, SHA1 was added later, and the code repository was ported to git in 2017.{{Cite web|url=https://github.com/cr-marcstevens/hashclash-old-svn-repo/tree/master/downloads|title=Old-SVN-hashclash/Downloads at master · cr-marcstevens/Old-SVN-hashclash|website=GitHub|access-date=2019-05-29|archive-date=2022-09-05|archive-url=https://web.archive.org/web/20220905053830/https://github.com/cr-marcstevens/old-svn-hashclash/tree/master/downloads|url-status=live}}

The project was used to create a rogue certificate authority certificate in 2009.Marc Stevens, Alexander Sotirov, Jacob Appelbaum, Arjen Lenstra, David Molnar, Dag Arne Osvik and Benne de Weger, "Short Chosen-Prefix Collisions for MD5 and the Creation of a Rogue CA Certificate", August 2009.