diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index f762203f7..a0b0bbf8b 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -2432,7 +2432,7 @@ function wp_ext2type( $ext ) {
 		'spreadsheet' => array( 'numbers',     'ods',  'xls',  'xlsx', 'xlsb',  'xlsm' ),
 		'interactive' => array( 'key', 'ppt',  'pptx', 'pptm', 'odp',  'swf' ),
 		'text'        => array( 'asc', 'csv',  'tsv',  'txt' ),
-		'archive'     => array( 'bz2', 'cab',  'dmg',  'gz',   'rar',  'sea',   'sit', 'sqx', 'tar', 'tgz',  'zip' ),
+		'archive'     => array( 'bz2', 'cab',  'dmg',  'gz',   'rar',  'sea',   'sit', 'sqx', 'tar', 'tgz',  'zip', '7z' ),
 		'code'        => array( 'css', 'htm',  'html', 'php',  'js' ),
 	));
 	foreach ( $ext2type as $type => $exts )
@@ -2598,6 +2598,8 @@ function get_allowed_mime_types() {
 		'tar' => 'application/x-tar',
 		'zip' => 'application/zip',
 		'gz|gzip' => 'application/x-gzip',
+		'rar' => 'application/rar',
+		'7z' => 'application/x-7z-compressed',
 		'exe' => 'application/x-msdownload',
 		// openoffice formats
 		'odt' => 'application/vnd.oasis.opendocument.text',