note 125013 added to function.intval
| From: | AnonyMoose@php.net | Date: | Fri, 15 May 2020 15:46:09 +0000 |
| Subject: | note 125013 added to function.intval | ||
| Groups: | php.notes | ||
| Request: | Send a blank email to php-notes+get-214636@lists.php.net to get a copy of this message | ||
As a warning, do not use this function alone for input validation.
Vulnerable example:
<?php
if(isset($_GET['id']) && intval($_GET['id']) > 0){
echo $id;
}
?>
The following requests would pass this filter:
/page.php?id=10
/page.php?id=10oops
/page.php?id=10<script>alert(1)</script>
/page.php?id=1' OR '1'='1
/page.php?id[]=<script>alert(1)</script>
Instead use the is_numeric() function for integer validation:
<?php
echo intval("10oops"); // 10
echo is_numeric("10oops"); // false
?>
Secure example:
<?php
if(isset($_GET['id']) && is_numeric($_GET['id']) &&
intval($_GET['id']) > 0){
echo $id;
}
?>
----
Server IP: 45.112.84.4
Probable Submitter: 38.142.137.34 (proxied: 162.224.118.61)
----
Manual Page -- http://php.net/manual/en/function.intval.php
Edit -- https://master.php.net/note/edit/125013
Del: integrated -- https://master.php.net/note/delete/125013/integrated
Del: useless -- https://master.php.net/note/delete/125013/useless
Del: bad code -- https://master.php.net/note/delete/125013/bad+code
Del: spam -- https://master.php.net/note/delete/125013/spam
Del: non-english -- https://master.php.net/note/delete/125013/non-english
Del: in docs -- https://master.php.net/note/delete/125013/in+docs
Del: other reasons-- https://master.php.net/note/delete/125013
Reject -- https://master.php.net/note/reject/125013
Search -- https://master.php.net/manage/user-notes.php