Britewave Digital
We also had came across such security notification two weeks back. This magento security issues affect all versions of Magento Community Edition and enables an attacker to remotely execute code on Magento software.
To overcome this problem either you have to upgrade your magento to the latest version 1.9.1.1 OR download following security patches from here https://www.magentocommerce.com/products/downloads/magento/
After downloading and installing the patches you can check here http://magento.com/security-patch
If the message will come "SAFE: This site appears to be safe." in green it means you are done.
You must be getting below error in your magento website admin just after the login.
Urgent: Immediately install Magento critical security patches

It is critical for you to download and install 2 previously-released security patches (SUPEE-5344 and SUPEE-1533) from the Magento Community Edition download page (https://www.magentocommerce.com/products/downloads/magento/). Please do this immediately, as Check Point Software Technologies has published a technical description of how they discovered the issue, which we feel might serve as a tutorial for implementing an attack against your website.
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