Index: src/wp-includes/revision.php
===================================================================
--- src/wp-includes/revision.php	(revision 27441)
+++ src/wp-includes/revision.php	(working copy)
@@ -371,7 +371,7 @@
 	if ( ! $post || empty( $post->ID ) )
 		return array();
 
-	$defaults = array( 'order' => 'DESC', 'orderby' => 'date ID', 'check_enabled' => true );
+	$defaults = array( 'order' => 'ASC', 'orderby' => 'date ID', 'check_enabled' => true );
 	$args = wp_parse_args( $args, $defaults );
 
 	if ( $args['check_enabled'] && ! wp_revisions_enabled( $post ) )
@@ -382,6 +382,8 @@
 	if ( ! $revisions = get_children( $args ) )
 		return array();
 
+	$revisions = array_reverse( $revisions );
+
 	return $revisions;
 }
 
Index: tests/phpunit/tests/post/revisions.php
===================================================================
--- tests/phpunit/tests/post/revisions.php	(revision 27441)
+++ tests/phpunit/tests/post/revisions.php	(working copy)
@@ -338,4 +338,33 @@
 			$this->assertTrue( user_can( $author_user_id, 'read_post', $revision->ID ) );
 		}
 	}
+
+	/**
+	 * @ticket 26042
+	 */
+	function test_revision_order() {
+		$ok = 0;
+		$reversed = 0;
+
+		for ( $i = 0; $i < 100; $i++ ) {
+			$post_id = $this->factory->post->create( array( 'post_title' => 'some-post', 'post_type' => 'post', 'post_content' => 'some_content' ) );
+
+			for ( $j = 1; $j < 3; $j++ ) {
+				wp_update_post( array( 'post_content' => 'updated post' . $j , 'ID' => $post_id ) );
+			}
+
+			$revisions = wp_get_post_revisions( $post_id );
+			$first = array_shift( $revisions );
+			$last = array_pop( $revisions );
+
+			if ( $first->ID < $last->ID ) {
+				$reversed++;
+			} else {
+				$ok++;
+			}
+		}
+
+		$this->assertEquals( 100, $ok );
+		$this->assertEquals( 0, $reversed );
+	}
 }