From 8ef530d46926178f82db7b1fb5bae71c7ee8af2b Mon Sep 17 00:00:00 2001
From: Pascal Birchler <pascal.birchler@gmail.com>
Date: Tue, 16 May 2017 08:40:36 +0000
Subject: [PATCH] Improve redirect handling

Merges[40689] to the 4.7 branch.

Built from https://develop.svn.wordpress.org/branches/4.7@40690


git-svn-id: http://core.svn.wordpress.org/branches/4.7@40553 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/class-http.php | 19 +++++++++++++++++++
 wp-includes/version.php    |  2 +-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/wp-includes/class-http.php b/wp-includes/class-http.php
index b9f5ab50fb..abee7aa0a5 100644
--- a/wp-includes/class-http.php
+++ b/wp-includes/class-http.php
@@ -306,6 +306,11 @@ class WP_Http {
 		// Ensure redirects follow browser behaviour.
 		$options['hooks']->register( 'requests.before_redirect', array( get_class(), 'browser_redirect_compatibility' ) );
 
+		// Validate redirected URLs.
+		if ( function_exists( 'wp_kses_bad_protocol' ) && $r['reject_unsafe_urls'] ) {
+			$options['hooks']->register( 'requests.before_redirect', array( get_class(), 'validate_redirects' ) );
+		}
+
 		if ( $r['stream'] ) {
 			$options['filename'] = $r['filename'];
 		}
@@ -466,6 +471,20 @@ class WP_Http {
 		}
 	}
 
+	/**
+	 * Validate redirected URLs.
+	 *
+	 * @since 4.7.5
+	 *
+	 * @throws Requests_Exception On unsuccessful URL validation
+	 * @param string $location URL to redirect to.
+	 */
+	public static function validate_redirects( $location ) {
+		if ( ! wp_http_validate_url( $location ) ) {
+			throw new Requests_Exception( __('A valid URL was not provided.'), 'wp_http.redirect_failed_validation' );
+		}
+	}
+
 	/**
 	 * Tests which transports are capable of supporting the request.
 	 *
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 0a894bcdff..c53f4d1099 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.7.5-alpha-40678';
+$wp_version = '4.7.5-alpha-40690';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.