diff --git a/give.php b/give.php
index 78d0cdfc9a..70ba172554 100644
--- a/give.php
+++ b/give.php
@@ -202,7 +202,7 @@ private function setup_constants() {
 
 			// Plugin version
 			if ( ! defined( 'GIVE_VERSION' ) ) {
-				define( 'GIVE_VERSION', '1.3.2' );
+				define( 'GIVE_VERSION', '1.3.3' );
 			}
 
 			// Plugin Folder Path
diff --git a/includes/libraries/class-wp-session.php b/includes/libraries/class-wp-session.php
index f0d115c7fe..8244f03537 100644
--- a/includes/libraries/class-wp-session.php
+++ b/includes/libraries/class-wp-session.php
@@ -5,9 +5,9 @@
  * Standardizes WordPress session data using database-backed options for storage.
  * for storing user session information.
  *
- * @package WordPress
+ * @package    WordPress
  * @subpackage Session
- * @since   3.7.0
+ * @since      3.7.0
  */
 
 /**
@@ -66,17 +66,20 @@ public static function get_instance() {
 	 * create a new session with that ID.
 	 *
 	 * @param $session_id
+	 *
 	 * @uses apply_filters Calls `wp_session_expiration` to determine how long until sessions expire.
 	 */
 	protected function __construct() {
-		if ( isset( $_COOKIE[WP_SESSION_COOKIE] ) ) {
-			$cookie = stripslashes( $_COOKIE[WP_SESSION_COOKIE] );
+		if ( isset( $_COOKIE[ WP_SESSION_COOKIE ] ) ) {
+			$cookie        = stripslashes( $_COOKIE[ WP_SESSION_COOKIE ] );
 			$cookie_crumbs = explode( '||', $cookie );
-
-			$this->session_id = $cookie_crumbs[0];
-			$this->expires = $cookie_crumbs[1];
+			if ( $this->is_valid_md5( $cookie_crumbs[0] ) ) {
+				$this->session_id = $cookie_crumbs[0];
+			} else {
+				$this->regenerate_id( true );
+			}
+			$this->expires     = $cookie_crumbs[1];
 			$this->exp_variant = $cookie_crumbs[2];
-
 			// Update the session expiration if we're past the variant time
 			if ( time() > $this->exp_variant ) {
 				$this->set_expiration();
@@ -87,9 +90,7 @@ protected function __construct() {
 			$this->session_id = $this->generate_id();
 			$this->set_expiration();
 		}
-
 		$this->read_data();
-
 		$this->set_cookie();
 
 	}
@@ -114,14 +115,14 @@ protected function __construct() {
 	 */
 	protected function set_expiration() {
 		$this->exp_variant = time() + (int) apply_filters( 'wp_session_expiration_variant', 24 * 60 );
-		$this->expires = time() + (int) apply_filters( 'wp_session_expiration', 30 * 60 );
+		$this->expires     = time() + (int) apply_filters( 'wp_session_expiration', 30 * 60 );
 	}
 
 	/**
 	 * Set the session cookie
 	 */
 	protected function set_cookie() {
-		@setcookie( WP_SESSION_COOKIE, $this->session_id . '||' . $this->expires . '||' . $this->exp_variant , $this->expires, COOKIEPATH, COOKIE_DOMAIN );
+		@setcookie( WP_SESSION_COOKIE, $this->session_id . '||' . $this->expires . '||' . $this->exp_variant, $this->expires, COOKIEPATH, COOKIE_DOMAIN );
 	}
 
 	/**
@@ -130,7 +131,7 @@ protected function set_cookie() {
 	 * @return string
 	 */
 	protected function generate_id() {
-		require_once( ABSPATH . 'wp-includes/class-phpass.php');
+		require_once( ABSPATH . 'wp-includes/class-phpass.php' );
 		$hasher = new PasswordHash( 8, false );
 
 		return md5( $hasher->get_random_bytes( 32 ) );
@@ -149,6 +150,17 @@ protected function read_data() {
 		return $this->container;
 	}
 
+	/**
+	 * Checks if is valid md5 string
+	 *
+	 * @param string $md5
+	 *
+	 * @return int
+	 */
+	protected function is_valid_md5( $md5 = '' ) {
+		return preg_match( '/^[a-f0-9]{32}$/', $md5 );
+	}
+
 	/**
 	 * Write the data from the current session to the data storage system.
 	 */
@@ -188,6 +200,7 @@ public function json_in( $data ) {
 
 		if ( is_array( $array ) ) {
 			$this->container = $array;
+
 			return true;
 		}
 
@@ -215,7 +228,7 @@ public function regenerate_id( $delete_old = false ) {
 	 * @return bool
 	 */
 	public function session_started() {
-		return !!self::$instance;
+		return ! ! self::$instance;
 	}
 
 	/**
diff --git a/includes/libraries/wp-session.php b/includes/libraries/wp-session.php
index bc87874662..c93b6225eb 100644
--- a/includes/libraries/wp-session.php
+++ b/includes/libraries/wp-session.php
@@ -5,9 +5,9 @@
  * Standardizes WordPress session data and uses either database transients or in-memory caching
  * for storing user session information.
  *
- * @package WordPress
+ * @package    WordPress
  * @subpackage Session
- * @since   3.7.0
+ * @since      3.7.0
  */
 
 /**
@@ -78,6 +78,7 @@ function wp_session_start() {
 
 	return $wp_session->session_started();
 }
+
 add_action( 'plugins_loaded', 'wp_session_start' );
 
 /**
@@ -113,6 +114,7 @@ function wp_session_write_close() {
 	$wp_session->write_data();
 	do_action( 'wp_session_commit' );
 }
+
 add_action( 'shutdown', 'wp_session_write_close' );
 
 /**
@@ -132,21 +134,19 @@ function wp_session_cleanup() {
 	if ( ! defined( 'WP_INSTALLING' ) ) {
 		$expiration_keys = $wpdb->get_results( "SELECT option_name, option_value FROM $wpdb->options WHERE option_name LIKE '_wp_session_expires_%'" );
 
-		$now = current_time( 'timestamp' );
+		$now              = current_time( 'timestamp' );
 		$expired_sessions = array();
 
-		foreach( $expiration_keys as $expiration ) {
+		foreach ( $expiration_keys as $expiration ) {
 			// If the session has expired
 			if ( $now > intval( $expiration->option_value ) ) {
 				// Get the session ID by parsing the option_name
 				$session_id = substr( $expiration->option_name, 20 );
-
-				if( (int) -1 === (int) $session_id ) {
+				if ( (int) -1 === (int) $session_id || ! preg_match( '/^[a-f0-9]{32}$/', $session_id ) ) {
 					continue;
 				}
-
 				$expired_sessions[] = $expiration->option_name;
-				$expired_sessions[] = "_wp_session_$session_id";
+				$expired_sessions[] = esc_sql( "_wp_session_$session_id" );
 			}
 		}
 
@@ -160,6 +160,7 @@ function wp_session_cleanup() {
 	// Allow other plugins to hook in to the garbage collection process.
 	do_action( 'wp_session_cleanup' );
 }
+
 add_action( 'wp_session_garbage_collection', 'wp_session_cleanup' );
 
 /**
@@ -170,4 +171,5 @@ function wp_session_register_garbage_collection() {
 		wp_schedule_event( current_time( 'timestamp' ), 'twicedaily', 'wp_session_garbage_collection' );
 	}
 }
+
 add_action( 'wp', 'wp_session_register_garbage_collection' );
diff --git a/readme.txt b/readme.txt
index 4228a56b3a..a4f479dbc8 100644
--- a/readme.txt
+++ b/readme.txt
@@ -129,6 +129,9 @@ We also really like WooCommerce. It's hands-down the most robust eCommerce platf
 
 == Changelog ==
 
+= 1.3.3 =
+* Fixed security vulnerability due to WP session IDs
+
 = 1.3.2 =
 * New: German/Deutsch translation for Give provided by Konrad - Thanks! :) - https://github.com/WordImpress/Give/issues/383
 * New: Polish/Polski translation provided by Emilia - Thanks! :) - https://github.com/WordImpress/Give/issues/418