Eccouncil Exam 312-39 Topic 9 Question 57 Discussion

An attacker exploits the logic validation mechanisms of an e-commerce website. He successfully purchases a product worth $100 for $10 by modifying the URL exchanged between the client and the server.

Original URL: http://www.buyonline.com/product.aspx?profile=12&debit=100 Modified URL: http://www.buyonline.com/product.aspx?profile=12&debit=10

Identify the attack depicted in the above scenario.