SUPEE-10266 contain multiple security enhancements that help close cross-site request forgery (CSRF), unauthorized data leak, and authenticated Admin user remote code execution vulnerabilities. These releases also include fixes for issues with image reloading and payments using one-step checkout. If you don't want to upgrade your PHP version to 1.9.3.6 then you can just install this security patch and it includes security feature added to Magento 1.9.3.6, so its equal to 1.9.3.6 Magento version.

Below is our process of installing security patch to Magento 1 websites.

• First, we will check is your website compatible for specific patch installation.
• We will take backup of required files.
• We will install the security patch to your website.
• We will test your website after install security patch.
• If found any bugs then we will spend up to our 2 hours for fixing issues.

What is not included in this service:

• Customization or fixing bugs of any third-party extension or module.
• Check if any core file replaced by security patch installation and fixing an issue related to core file replaced by the security patch.

What we need from your side:

- Magento admin login detail.
- FTP login detail.
- Cpanel login detail.
- Please submit your details securely from Customer Support Page.

NOTE: Some conditions apply.
Usually, it will take approx 2-4 working days (depending on the complexity of the website)