Implement token system to fix CSRF vulnerabilities

Specially crafted pages can force authenticated users to unknowingly perform
actions on the AUR website despite being on an attacker's website. This
cross-site request forgery (CSRF) vulnerability applies to all POST data on
the AUR.

Implement a token system using a double submit cookie. Have a hidden form
value on every page containing POST forms. Use the newly added check_token() to
verify the token sent via POST matches the "AURSID" cookie value. Random
nature of the token limits potential for CSRF.

Signed-off-by: canyonknight <canyonknight@gmail.com>
Signed-off-by: Lukas Fleischer <archlinux@cryptocrack.de>
This commit is contained in:
canyonknight 2012-06-23 14:40:11 -04:00 committed by Lukas Fleischer
parent bfb25807c4
commit 2c93f0a98f
13 changed files with 82 additions and 46 deletions

View file

@ -16,7 +16,11 @@ if (isset($_COOKIE["AURSID"])) {
if ($atype == "Trusted User" OR $atype == "Developer") {
$dbh = db_connect();
if (!empty($_POST['addVote'])) {
if (!empty($_POST['addVote']) && !check_token()) {
$error = __("Invalid token for user action.");
}
if (!empty($_POST['addVote']) && check_token()) {
$error = "";
if (!empty($_POST['user'])) {
@ -99,6 +103,7 @@ if ($atype == "Trusted User" OR $atype == "Developer") {
<b><?php print __('Proposal') ?></b><br />
<textarea name='agenda' rows='25' cols='80'><?php if (!empty($_POST['agenda'])) { print htmlentities($_POST['agenda']); } ?></textarea><br />
<input type='hidden' name='addVote' value='1' />
<input type='hidden' name='token' value='<?php print htmlspecialchars($_COOKIE['AURSID']) ?>' />
<input type='submit' class='button' value='<?php print __('Submit'); ?>' />
</p>
</form>