A cross site request forgery (CSRF) issue has been identified in the SWFUpload library that XenForo uses. This issue may allow an attacker to make requests and carry out actions as you or one of your members. This issue affects all versions of XenForo available prior to this announcement. We recommend all customers take steps to apply a fix as soon as possible. If you have any questions about applying a fix, please post in the appropriate forum or submit a ticket. Applying a Fix: Upgrading XenForo versions 1.2.7, 1.3.6 and 1.4.1 include a fix for this issue. To apply the fix, you may upgrade in the standard way to the appropriate version: Customers running 1.2 or earlier should upgrade to 1.2.7, 1.3.6 or 1.4.1. Customers running 1.3 should upgrade to 1.3.6 or 1.4.1. Customers running 1.4 should upgrade to 1.4.1. Customers with an active license may download these versions from their customer area. Full details for how to install and upgrade XenForo can be found in the XenForo Manual. Applying a Fix: Patching Alternatively, this issue can be fixed by applying the patch in the attached file. You should simply overwrite the existing js/swfupload/Flash/swfupload.swf file with the version attached to this message. The file can be found at the same path within the attachment.