Editing Personal identification number (section)

===Implementation flaws===
In 2002, two PhD students at [[University of Cambridge|Cambridge University]], Piotr Zieliński and Mike Bond, discovered a security flaw in the PIN generation system of the [[IBM 3624]], which was duplicated in most later hardware. Known as the [[decimalization table attack]], the flaw would allow someone who has access to a bank's computer system to determine the PIN for an ATM card in an average of 15 guesses.<ref name="decimalization">
{{cite journal
  |author1=Zieliński, P  |author2=Bond, M
   |name-list-style=amp | title = Decimalisation table attacks for PIN cracking
  | version =02453
  | publisher = University of Cambridge Computer Laboratory
  | date = February 2003
  | url = http://www.cl.cam.ac.uk/TechReports/UCAM-CL-TR-560.pdf
  | access-date = 2006-11-24}}</ref><ref name="decimalization-media">{{cite web
  | url=http://www.cl.cam.ac.uk/~mkb23/media-coverage.html
  | title=Media coverage
  | publisher=University of Cambridge Computer Laboratory
  | access-date=2006-11-24
  | archive-date=2018-10-20
  | archive-url=https://web.archive.org/web/20181020060141/https://www.cl.cam.ac.uk/~mkb23/media-coverage.html
  | url-status=dead
  }}</ref>