Assume that you run an XML validation task in Microsoft SQL Server 2012 Integration Service (SSIS 2012) or SQL Server 2014 Integration Service (SSIS 2014). When the input source file is in read-only mode, SSIS throws an "Access Denied" error.
This issue occurs because the default access mode to source file is Read/Write in SSIS 2012. Therefore, when SSIS 2012 opens a read-only source file in the default file access mode, there will be an IOException that results in the "Access Denied" error.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.