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From f06a069c462d37c2e009f6d1d93b8c8e7b713393 Mon Sep 17 00:00:00 2001
From: Stanislav Malyshev <stas@php.net>
Date: Tue, 1 Sep 2015 00:14:15 -0700
Subject: [PATCH] Fix bug #70365 - use-after-free vulnerability in
unserialize() with SplObjectStorage
---
ext/spl/spl_observer.c | 2 ++
ext/spl/tests/bug70365.phpt | 50 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 52 insertions(+)
create mode 100644 ext/spl/tests/bug70365.phpt
Index: php5-5.3.3.1/ext/spl/spl_observer.c
===================================================================
--- php5-5.3.3.1.orig/ext/spl/spl_observer.c 2015-10-28 13:30:23.000000000 +0100
+++ php5-5.3.3.1/ext/spl/spl_observer.c 2015-10-28 13:31:06.000000000 +0100
@@ -647,6 +648,7 @@
zval_ptr_dtor(&pentry);
goto outexcept;
}
+ var_push_dtor(&var_hash, &pentry);
if(Z_TYPE_P(pentry) != IS_OBJECT) {
zval_ptr_dtor(&pentry);
goto outexcept;
@@ -658,6 +660,7 @@
zval_ptr_dtor(&pinf);
goto outexcept;
}
+ var_push_dtor(&var_hash, &pinf);
}
pelement = spl_object_storage_get(intern, pentry TSRMLS_CC);
Index: php5-5.3.3.1/ext/spl/tests/bug70365.phpt
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ php5-5.3.3.1/ext/spl/tests/bug70365.phpt 2015-10-28 13:30:23.000000000 +0100
@@ -0,0 +1,50 @@
+--TEST--
+SPL: Bug #70365 yet another use-after-free vulnerability in unserialize() with SplObjectStorage
+--FILE--
+<?php
+class obj {
+ var $ryat;
+ function __wakeup() {
+ $this->ryat = 1;
+ }
+}
+
+$fakezval = ptr2str(1122334455);
+$fakezval .= ptr2str(0);
+$fakezval .= "\x00\x00\x00\x00";
+$fakezval .= "\x01";
+$fakezval .= "\x00";
+$fakezval .= "\x00\x00";
+
+$inner = 'x:i:1;O:8:"stdClass":0:{},i:1;;m:a:0:{}';
+$exploit = 'a:5:{i:0;i:1;i:1;C:16:"SplObjectStorage":'.strlen($inner).':{'.$inner.'}i:2;O:3:"obj":1:{s:4:"ryat";R:3;}i:3;R:6;i:4;s:'.strlen($fakezval).':"'.$fakezval.'";}';
+
+$data = unserialize($exploit);
+
+var_dump($data);
+
+function ptr2str($ptr)
+{
+ $out = '';
+ for ($i = 0; $i < 8; $i++) {
+ $out .= chr($ptr & 0xff);
+ $ptr >>= 8;
+ }
+ return $out;
+}
+--EXPECTF--
+array(5) {
+ [0]=>
+ int(1)
+ [1]=>
+ &int(1)
+ [2]=>
+ object(obj)#%d (1) {
+ ["ryat"]=>
+ &int(1)
+ }
+ [3]=>
+ int(1)
+ [4]=>
+ string(24) "%s"
+}
|
