Magento Open Source, 1.9.x

Magento 1.x Security Patch Notice
For Magento Open Source 1.5 to 1.9, Magento is providing software security patches through June 2020 to ensure those sites remain secure and compliant. Visit our information page for more details about our software maintenance policy and other considerations for your business.

Direct Post

Magento Open Source incorporates the Direct Post method for payments made through Authorize.Net. When payments are made with Direct Post, Authorize.Net handles all steps in the transaction process— such as payment data collection, data submission, and response to the customer—while the customer remains in your store.

Deprecation Notice: Authorize.Net has deprecated the use of MD5 Hash. When configuring, enter a Signature Key using SHA-512. These instructions include the updated step. Payment processing will not complete until you add the correct Signature Key. For details, see Authorize.Net's MD5 Hash End of Life & Signature Key Replacement and What is a Signature Key. To install the patch, see the Magento KB article Update Authorize.Net Direct Post from MD5 to SHA-512.

Checkout Using Authorize.Net Direct Post