If you suspect that your site is compromised, follow this action plan without delay.
Run a scan to establish the security status of your Magento store. MageReport.com is a highly regarded service that is available at no charge to members of the Magento community.
Hire a qualified consultant or online service to clean your site of all malicious code. Some Magento community members recommend Sucuri Website Malware Removal. Check the
/mediafolder for leftover executable code. Remove all unknown Admin users and reset all Admin passwords.
Keep your Magento installation up-to-date with the most current release. If using an older version, apply all security patches as they become available. Review and follow Magento Security Best Practices. Subscribe to Magento Security Alerts.
If you think that you have found a specific vulnerability in Magento, send a description of the problem with technical details to firstname.lastname@example.org.
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