diff --git a/src/wp-includes/query.php b/src/wp-includes/query.php
index 96148ba20e..d53ec42788 100644
--- a/src/wp-includes/query.php
+++ b/src/wp-includes/query.php
@@ -3193,7 +3193,7 @@ class WP_Query {
 				$cgroupby = "$wpdb->comments.comment_id";
 			} else { // Other non singular e.g. front
 				$cjoin = "JOIN $wpdb->posts ON ( $wpdb->comments.comment_post_ID = $wpdb->posts.ID )";
-				$cwhere = "WHERE post_status = 'publish' AND comment_approved = '1'";
+				$cwhere = "WHERE ( post_status = 'publish' OR ( post_status = 'inherit' && post_type = 'attachment' ) ) AND comment_approved = '1'";
 				$cgroupby = '';
 			}
 
diff --git a/tests/phpunit/tests/query/conditionals.php b/tests/phpunit/tests/query/conditionals.php
index fd228910bb..a1f3665486 100644
--- a/tests/phpunit/tests/query/conditionals.php
+++ b/tests/phpunit/tests/query/conditionals.php
@@ -57,6 +57,13 @@ class Tests_Query_Conditionals extends WP_UnitTestCase {
 		$this->assertQueryTrue('is_feed', 'is_single', 'is_singular', 'is_comment_feed');
 	}
 
+	function test_attachment_comments_feed() {
+		$attachment_id = self::factory()->post->create( array( 'post_type' => 'attachment' ) );
+		self::factory()->comment->create_post_comments( $attachment_id, 2 );
+		$this->go_to( get_post_comments_feed_link( $attachment_id ) );
+		$this->assertQueryTrue( 'is_feed', 'is_attachment', 'is_single', 'is_singular', 'is_comment_feed' );
+	}
+
 	function test_page() {
 		$page_id = self::factory()->post->create( array( 'post_type' => 'page', 'post_title' => 'about' ) );
 		$this->go_to( get_permalink( $page_id ) );
diff --git a/tests/phpunit/tests/query/results.php b/tests/phpunit/tests/query/results.php
index 30a32909c8..fa544319b1 100644
--- a/tests/phpunit/tests/query/results.php
+++ b/tests/phpunit/tests/query/results.php
@@ -703,4 +703,19 @@ class Tests_Query_Results extends WP_UnitTestCase {
 		$result2 = $this->q->query( array( 'title' => 'Tacos', 'fields' => 'ids' ) );
 		$this->assertCount( 0, $result2 );
 	}
+
+	/**
+	 * @ticket 15610
+	 */
+	public function test_main_comments_feed_includes_attachment_comments() {
+		$attachment_id = self::factory()->post->create( array( 'post_type' => 'attachment' ) );
+		$comment_id = self::factory()->comment->create( array( 'comment_post_ID' => $attachment_id, 'comment_approved' => '1' ) );
+
+		$this->q->query( array( 'withcomments' => 1, 'feed' => 'feed' ) );
+
+		$this->assertTrue( $this->q->have_comments() );
+
+		$feed_comment = $this->q->next_comment();
+		$this->assertEquals( $comment_id, $feed_comment->comment_ID );
+	}
 }