diff -Naur php-5.3.29-original/ext/standard/tests/serialize/bug68594.phpt php-5.3.29/ext/standard/tests/serialize/bug68594.phpt
--- php-5.3.29-original/ext/standard/tests/serialize/bug68594.phpt	1970-01-01 00:00:00.000000000 +0000
+++ php-5.3.29/ext/standard/tests/serialize/bug68594.phpt	2015-01-24 13:14:16.222248839 +0000
@@ -0,0 +1,23 @@
+--TEST--
+Bug #68545 Use after free vulnerability in unserialize()
+--FILE--
+<?php
+for ($i=4; $i<100; $i++) {
+	$m = new StdClass();
+
+	$u = array(1);
+
+	$m->aaa = array(1,2,&$u,4,5);
+	$m->bbb = 1;
+	$m->ccc = &$u;
+	$m->ddd = str_repeat("A", $i);
+
+	$z = serialize($m);
+	$z = str_replace("bbb", "aaa", $z);
+	$y = unserialize($z);
+	$z = serialize($y);
+}
+?>
+===DONE===
+--EXPECTF--
+===DONE===
diff -Naur php-5.3.29-original/ext/standard/var_unserializer.c php-5.3.29/ext/standard/var_unserializer.c
--- php-5.3.29-original/ext/standard/var_unserializer.c	2015-01-24 13:05:17.310236430 +0000
+++ php-5.3.29/ext/standard/var_unserializer.c	2015-01-24 13:09:14.269241886 +0000
@@ -298,6 +298,9 @@
 		} else {
 			/* object properties should include no integers */
 			convert_to_string(key);
+			if (zend_symtable_find(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&old_data)==SUCCESS) {
+				var_push_dtor(var_hash, old_data);
+			}
 			zend_hash_update(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, &data,
 					sizeof data, NULL);
 		}
diff -Naur php-5.3.29-original/ext/standard/var_unserializer.re php-5.3.29/ext/standard/var_unserializer.re
--- php-5.3.29-original/ext/standard/var_unserializer.re	2015-01-24 13:05:17.310236430 +0000
+++ php-5.3.29/ext/standard/var_unserializer.re	2015-01-24 13:07:59.593240167 +0000
@@ -304,6 +304,9 @@
 		} else {
 			/* object properties should include no integers */
 			convert_to_string(key);
+			if (zend_symtable_find(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&old_data)==SUCCESS) {
+				var_push_dtor(var_hash, old_data);
+			}
 			zend_hash_update(ht, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, &data,
 					sizeof data, NULL);
 		}