For securing forms, when do I issue the token?

Posted by AQuestionADayKeepsTheDrAway on Stack Overflow See other posts from Stack Overflow or by AQuestionADayKeepsTheDrAway
Published on 2010-06-03T16:51:17Z Indexed on 2010/06/03 16:54 UTC
Read the original article Hit count: 157

Filed under:

php

|

csrf

So, I have a form, to make it a little more secure and potentially help prevent CSRF attacks I want to add a random token value in a hidden field that value is also stored server side in my session data.

When should I issue a new token? Per form? Per page load where there is any form? Per session? I can render it invalid as soon as a form is successfully submitted but I'm wondering when to generate one.

I ask as if I issue it per form or per page do I not risk the chance of a duplicate token value overwriting the existing (valid) token if a user opens a separate window but submitting the first form (with the now overwritten value)?

© Stack Overflow or respective owner

Related posts about php

Magento, NGINX, PHP-FPM, APC, MEMCACHED, 16gb Ram CentOS, Spiking PHP-FPM to 100% CPU

as seen on Server Fault - Search for 'Server Fault'
I have been trying to resolve my issue of spiking cpu caused by php-fpm processes. I've reduced the php-fpm config settings to: pm = ondemand pm.max_children = 12 pm.start_servers = 2 pm.min_spare_servers = 2 pm.max_spare_servers = 10 pm.max_requests = 500 php_admin_value[memory_limit] = 128M Problem… >>> More
PHP Pear Installation on CentOS

as seen on Server Fault - Search for 'Server Fault'
[root@ip ~]# yum install php-pear* Reducing CentOS-5 Testing to included packages only Finished Setting up Install Process Package 1:php-pear-1.8.1-2.el5.centos.noarch already installed and latest versio … >>> More
Apache configurations for php "AddType text/html php" or "AddType application/x-httpd-php php .php"

as seen on Server Fault - Search for 'Server Fault'
I am taking over an application server and discover that it contain the following settings: AddType text/html php Although it works, but my understanding is that it should set as following: AddType application/x-httpd-php php .php What are the key differences between the two settings?… >>> More
mod_rewrite settings causes server to throw HTTP 500 errors instead of 404

as seen on Server Fault - Search for 'Server Fault'
Hello. I have a server with VBulletin forum (working under Apache 2.2, CentOS). The default settings for it in .htaccess are as follows: RewriteEngine on RewriteCond %{HTTP_HOST} ^gsmforum\.ru RewriteRule (.*) http://www.gsmforum.ru/$1 [R=301,L] # If you are having problems or are using VirtualDocumentRoot… >>> More
Problems installing Memcache (PECL extension)

as seen on Server Fault - Search for 'Server Fault'
I have installed memcached fine, and now I will need to install PECL extension memcache. Im running RedHat x86_64 es5. The installation gives me this: downloading memcache-2.2.6.tgz ... Starting to download memcache-2.2.6.tgz (35,957 bytes) ..........done: 35,957 bytes 11 source files, building running:… >>> More

Related posts about csrf

Django CSRF framework cannot be disabled and is breaking my site

as seen on Stack Overflow - Search for 'Stack Overflow'
The django csrf middleware can't be disabled. I've commented it out from my Middleware of my project but my logins are failing due to missing CSRF issues. I'm working from the Django trunk. How can CSRF cause issues if it is not enabled in middleware? I have to disable it because there are lots… >>> More
Make CSRF middleware work in Django's 404 error pages

as seen on Stack Overflow - Search for 'Stack Overflow'
I put a login box alone with a keyword search box in 404.html in a Django project so in case a 404 error is raised, visitors get more options to jump to other parts. But the CSRF middleware doesn't work in 404 error page with no csrf token rendered. I tried move 'django.middleware.csrf.CsrfViewMiddleware'… >>> More
CSRF (Cross-site request forgery) attack example and prevention in PHP

as seen on Stack Overflow - Search for 'Stack Overflow'
I have an website where people can place a vote like this: http://mysite.com/vote/25 This will place a vote on item 25. I want to only make this available for registered users, and only if they want to do this. Now I know when someone is busy on the website, and someone gives them a link like this: http://mysite… >>> More
Having a POST'able API and Django's CSRF Middleware

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a Django webapp that has both a front-end, web-accessible component and an API that is accessed by a desktop client. However, now with the new CSRF middleware component, API requests from the desktop client that are POST'ed get a 403. I understand why this is happening, but what is the proper… >>> More
HtmlUnit to login (post form) to csrf enable website

as seen on Stack Overflow - Search for 'Stack Overflow'
I am posting a form using HTMLUnit webClient by putting the username and password but it could not logging me in. When i research then found out that they have enable csrf on post request so native web browser is required. Is there any way to login (post form) in csrf enable website using HTMLUnit… >>> More