Backported from 5.6.25 by Remi.

From 1f6078e4a5c67733bfdbd20bb2706501ac56a344 Mon Sep 17 00:00:00 2001
From: Stanislav Malyshev <stas@php.net>
Date: Wed, 10 Aug 2016 23:43:56 -0700
Subject: [PATCH] Fix for bug #72790 and bug #72799

---
 ext/wddx/tests/bug72790.phpt | 35 +++++++++++++++++++++++++++++++++++
 ext/wddx/tests/bug72799.phpt | 28 ++++++++++++++++++++++++++++
 ext/wddx/wddx.c              | 14 +++++++++-----
 3 files changed, 72 insertions(+), 5 deletions(-)
 create mode 100644 ext/wddx/tests/bug72790.phpt
 create mode 100644 ext/wddx/tests/bug72799.phpt

diff --git a/ext/wddx/tests/bug72790.phpt b/ext/wddx/tests/bug72790.phpt
new file mode 100644
index 0000000..a60524b
--- /dev/null
+++ b/ext/wddx/tests/bug72790.phpt
@@ -0,0 +1,35 @@
+--TEST--
+Bug 72790: wddx_deserialize null dereference with invalid xml
+--SKIPIF--
+<?php
+if (!extension_loaded('wddx')) {
+    die('skip. wddx not available');
+}
+?>
+--FILE--
+<?php
+
+$xml = <<< XML
+<?xml version='1.0' ?>
+<!DOCTYPE wddxPacket SYSTEM 'wddx_0100.dtd'>
+<wddxPacket version='1.0'>
+        |array>
+                <var name="XXXX">
+                        <boolean value="this">
+                        </boolean>
+                </var>
+                <var name="YYYY">
+                        <var name="UUUU">
+                                <var name="EZEZ">
+                                </var>
+                        </var>
+                </var>
+        </array>
+</wddxPacket>
+XML;
+
+$array = wddx_deserialize($xml);
+var_dump($array);
+?>
+--EXPECT--
+NULL
\ No newline at end of file
diff --git a/ext/wddx/tests/bug72799.phpt b/ext/wddx/tests/bug72799.phpt
new file mode 100644
index 0000000..5861d55
--- /dev/null
+++ b/ext/wddx/tests/bug72799.phpt
@@ -0,0 +1,28 @@
+--TEST--
+Bug #72799: wddx_deserialize null dereference in php_wddx_pop_element
+--SKIPIF--
+<?php
+if (!extension_loaded('wddx')) {
+    die('skip. wddx not available');
+}
+?>
+--FILE--
+<?php
+
+$xml = <<<XML
+<?xml version='1.0'?>
+<!DOCTYPE wddxPacket SYSTEM 'wddx_0100.dtd'>
+<wddxPacket version="1.0">
+    <var name="XXXX">
+        <boolean value="1">
+            <dateTime>1998-06-12T04:32:12+00</dateTime>
+        </boolean>
+    </var>
+</wddxPacket>
+XML;
+
+$array = wddx_deserialize($xml);
+var_dump($array);
+?>
+--EXPECT--
+NULL
\ No newline at end of file
diff --git a/ext/wddx/wddx.c b/ext/wddx/wddx.c
index 1b2d103..d7bd295 100644
--- a/ext/wddx/wddx.c
+++ b/ext/wddx/wddx.c
@@ -939,10 +939,10 @@ static void php_wddx_pop_element(void *user_data, const XML_Char *name)
 		if (!ent1->data) {
 			if (stack->top > 1) {
 				stack->top--;
+				efree(ent1);
 			} else {
 				stack->done = 1;
 			}
-			efree(ent1);
 			return;
 		}
 
@@ -981,7 +981,7 @@ static void php_wddx_pop_element(void *user_data, const XML_Char *name)
 			wddx_stack_top(stack, (void**)&ent2);
 
 			/* if non-existent field */
-			if (ent2->type == ST_FIELD && ent2->data == NULL) {
+			if (ent2->data == NULL) {
 				zval_ptr_dtor(&ent1->data);
 				efree(ent1);
 				return;
@@ -1172,9 +1172,13 @@ int php_wddx_deserialize_ex(char *value, int vallen, zval *return_value)
 
 	if (stack.top == 1) {
 		wddx_stack_top(&stack, (void**)&ent);
-		*return_value = *(ent->data);
-		zval_copy_ctor(return_value);
-		retval = SUCCESS;
+		if(ent->data == NULL) {
+			retval = FAILURE;
+		} else {
+			*return_value = *(ent->data);
+			zval_copy_ctor(return_value);
+			retval = SUCCESS;
+		}
 	} else {
 		retval = FAILURE;
 	}