diff --git a/src/wp-includes/post.php b/src/wp-includes/post.php
index 334a0b8c0c..f7654f0f72 100644
--- a/src/wp-includes/post.php
+++ b/src/wp-includes/post.php
@@ -5091,11 +5091,16 @@ function wp_attachment_is( $type, $post_id = 0 ) {
 	}
 
 	$check = wp_check_filetype( $file );
-	if ( empty( $check['ext'] ) || 'import' !== $post->post_mime_type ) {
+	if ( empty( $check['ext'] ) ) {
 		return false;
 	}
+
 	$ext = $check['ext'];
 
+	if ( 'import' !== $post->post_mime_type ) {
+		return $type === $ext;
+	}
+
 	switch ( $type ) {
 	case 'image':
 		$image_exts = array( 'jpg', 'jpeg', 'jpe', 'gif', 'png' );
diff --git a/tests/phpunit/tests/post/attachments.php b/tests/phpunit/tests/post/attachments.php
index f7e8f9c826..833a56f1e3 100644
--- a/tests/phpunit/tests/post/attachments.php
+++ b/tests/phpunit/tests/post/attachments.php
@@ -439,4 +439,29 @@ class Tests_Post_Attachments extends WP_UnitTestCase {
 		$_SERVER['HTTP_HOST'] = $http_host;
 	}
 
+	public function test_wp_attachment_is() {
+		$filename = DIR_TESTDATA . '/images/test-image.jpg';
+		$contents = file_get_contents( $filename );
+
+		$upload = wp_upload_bits( basename( $filename ), null, $contents );
+		$attachment_id = $this->_make_attachment( $upload );
+
+		$this->assertTrue( wp_attachment_is_image( $attachment_id ) );
+		$this->assertTrue( wp_attachment_is( 'image', $attachment_id ) );
+		$this->assertFalse( wp_attachment_is( 'audio', $attachment_id ) );
+		$this->assertFalse( wp_attachment_is( 'video', $attachment_id ) );
+	}
+
+	public function test_wp_attachment_is_default() {
+		$filename = DIR_TESTDATA . '/images/test-image.psd';
+		$contents = file_get_contents( $filename );
+
+		$upload = wp_upload_bits( basename( $filename ), null, $contents );
+		$attachment_id = $this->_make_attachment( $upload );
+
+		$this->assertFalse( wp_attachment_is_image( $attachment_id ) );
+		$this->assertTrue( wp_attachment_is( 'psd', $attachment_id ) );
+		$this->assertFalse( wp_attachment_is( 'audio', $attachment_id ) );
+		$this->assertFalse( wp_attachment_is( 'video', $attachment_id ) );
+	}
 }