Switch -OM[-|1][=list] - propagate Mark of the Web


Internet browsers can add so called Mark of the Web to downloaded files. It is stored in Zone.Identifier NTFS alternate data stream and provides the information about file security zone, original location also as other optional fields. Various software can use it for security purposes.

By default WinRAR copies contents the archive Mark of the Web to files extracted from this archive if it is allowed by "Propagate Mark of the Web" option in Security settings dialog, but this command line switch can be used to override it.

If this switch is followed by '1', all Mark of the Web fields are copied from archive to extracted files. For -om without '1' only the security zone value is propagated. Information contained in other fields might be useful to identify a file source, but it can disclose the potentially confidential file download location, IP address and other sensitive information if file is shared with other persons. So the default behavior of this switch without '1' modifier is to omit all fields except the security zone value.

Optional '-' parameter prohibits Mark of the Web propagation and can be used to override settings stored in rar.ini configuration file or RARINISWITCHES environment variable.

Optional <list> parameter defines the list of file extensions separated by semicolons. For example, -om=doc;exe;bat will force WinRAR to propagate Mark of the Web only for *.doc, *.exe and *.bat files. It is also allowed to specify wildcard file masks in the list, so -om=*.doc;*.exe;*.bat will work too. If list is omitted, all extracted files are assumed.

Switch -os can be used to preserve source files Mark of the Web when archiving, so it is restored when extracting.

Examples

  1. propagate the archive Mark of the Web to all extracted files. Include security zone value only

WinRAR x -om archive.rar

  1. propagate the archive Mark of the Web to *.doc and *.exe. Include all Mark of the Web fields

WinRAR x -om1=doc;exe archive.rar