From skalore@sd2600.net Tue Sep 28 03:05:18 1999 From: Ben Resent-From: mea culpa To: Defcon Mailing List , Yashy Hack , BUGTRAQ Resent-To: jericho@attrition.org Date: Wed, 22 Sep 1999 00:46:11 -0700 Reply-To: yashy-hack@yashy.com Subject: [yh] Coinstar Vulnerability Advisory I post this after initially displaying this on my website and notifying Coinstar several months ago without a response. San Diego 2600 Advisory by skalore: Coinstar is a public company CNSTR on NASDAQ that makes machines that counts miscellaneous coins you enter in it, and prints out a voucher to return to any checker at the grocery store to get dollars. It is a pretty convienent idea. The problem lies within the fact that it takes a 9 cent charge off of every dollar for a processing fee. So what happens if you enter less then 9 cents, for example a penny? Well, I tried exactly that. I took one penny and deposited it into the Coinstar machine and it returned it to me, BUT it displayed $0.01 on the status screen. Hrmm.. was it actually counting the penny then giving it back to me? So I pressed Done and waited for my voucher to be printed, after about 30 seconds it printed my voucher and it said on it, $0.01! I actually doubled my money, one penny to two pennies. The next thing I did was to see if after the coin was returned to me if I could just continue to deposit it back into the machine during that one session, so I kept on doing that, and everything worked up until $0.15 when it locked the machine. So the point is the max amount you can put in this way is $0.14 cents. Imagine, if your doing grocery shopping and your bill comes to $20, instead of cash you just pull out 143 vouchers each $0.14 cents and your bill is paid for, and it didn't even cost you your penny! www.sd2600.net/~skalore/coinstar.html As always this information is freely distributed and no one involved actually encourages fraud using the Coinstar machine, but this is for informational purposes only. -- ------------------ skalore@sd2600.net Chairman of ToorCon (http://www.toorcon.com) Founder of San Diego 2600 (http://www.sd2600.net) "We hold these truths to be self-evident, that all men are created equal.." - Declaration of Independence ------------------ _______ Yashy-Hack http://yashy.com/~monarc/ to unsubscribe: echo unsubscribe | mail yashy-hack-request@yashy.com