A new patch (SUPEE-10497) is available for merchants using Magento Open Source 1.9.1.1. This patch replaces SUPEE-10266 (released September 14, 2017) and SUPEE-10415 (released November 28, 2017).
Do I need to patch?
This issue affects users of Magento Open Source 1.9.1.1 only. Users of Magento Commerce, or any other version of Magento Open Source, are not affected.
This patch combines SUPEE-10415 and SUPEE-10266 for Magento Open Source 1.9.1.1. To install, remove both patches first then install SUPEE-10497.