You need SSH (shell) access to download and apply the patch. You need only three commands, CD, WGET and BASH, to navigate, download and apply the patch.
Step 1: Make a backup
There’s a chance that certain plugins or elements in your webshop aren’t compatible with the Magento patch. That’s why we always recommend you to make a backup first, in case something goes wrong.
Step 2: Log on to SSH (shell)
Log on to the shell server. If you don’t how to log on, contact your hosting provider or technical contact
Step 3: Download the patch
To download the correct patch for your webshop you need to know what version of Magento your using, here you need 126.96.36.199 .
Download the patch(es) you need via the Magento downloads page.
Step 4: Apply the patch
The command BASH will apply the patch you just downloaded:
Let’s assume here that the patch name is: patch_supee-5994.sh . Your actual command would look like this:
Step 5: Clear your cache
It’s important to flush the Magento cache after applying the patch. Flushing your caches can be done in the back-end of your Magento shop under Cache management. Don’t forget to flush your OPcode or APC cache as well!
Step 6: Check your shop
Don’t forget to check your shop for vulnerabilities after patching and flushing your caches. Magento’s Security Patch Page provides a list of signs to look out for to determine whether your site is comprised or not.