We have just released Magento version 1.0.19870.1 that includes a patch for the Base URL security issue described in detail the the blog post here.

This patch adds validation and a warning message in the admin panel if the configuration value for Base URL is {{base_url}}. The installation wizard was modified so it requests a valid Base URL value during the installation process.

There are no other updates in this version.

If you are using Magento version 1.0.19870 or lower we highly recommend upgrading to Magento version 1.0.19870.1

Instructions for Upgrading Magento with a full package, via SVN, via the MagentoConnect Manager and using SSH shell access are available in this wiki post.

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