Brian Mastenbrook discovered that rails, the MVC ruby based framework geared for web application development, is prone to cross-site scripting attacks via malformed strings in the form helper. For the stable distribution , this problem has been fixed in version 2.1.0-7. For the oldstable distribution security support has been discontinued. It has been reported that rails in oldstable is unusable and several features that are affected by security issues are broken due to programming issues. It is highly recommended to upgrade to the version in stable . For the testing distribution and the unstable distribution , this problem has been fixed in version 2.2.3-1. We recommend that you upgrade your rails packages.