From c5c7691c85c84a1b5e1efbabefbfedeff7867164 Mon Sep 17 00:00:00 2001
From: Andrew Nacin <nacin@git.wordpress.org>
Date: Tue, 8 Apr 2014 18:07:28 +0000
Subject: [PATCH] Harden HMAC verification. props duck_. [28053] for 3.7.

git-svn-id: https://develop.svn.wordpress.org/branches/3.7@28055 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/pluggable.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wp-includes/pluggable.php b/src/wp-includes/pluggable.php
index 6839b015ac..e340fc725c 100644
--- a/src/wp-includes/pluggable.php
+++ b/src/wp-includes/pluggable.php
@@ -546,7 +546,7 @@ function wp_validate_auth_cookie($cookie = '', $scheme = '') {
 	$key = wp_hash($username . $pass_frag . '|' . $expiration, $scheme);
 	$hash = hash_hmac('md5', $username . '|' . $expiration, $key);
 
-	if ( $hmac != $hash ) {
+	if ( hash_hmac( 'md5', $hmac, $key ) !== hash_hmac( 'md5', $hash, $key ) ) {
 		do_action('auth_cookie_bad_hash', $cookie_elements);
 		return false;
 	}