unchecked unserialize usage in WordPress-Functionality-Plugin-Skeleton/functionality-plugin-skeleton.php
I
Ian Dunn
Submitted None
Actions:
Reported by
e3amn2l
Vulnerability Details
Technical details and impact analysis
in:
https://github.com/iandunn/WordPress-Functionality-Plugin-Skeleton/blob/547216caf1bef2664ec3920a9c749191dea13aeb/functionality-plugin-skeleton.php#L108
there is usage of unserialize function
```
public function block_plugin_updates( $request, $url ) {
if ( 0 !== strpos( $url, self::PLUGIN_UPDATE_CHECK_URL ) ) // todo moving to https at some point, if hasn't already
return $request;
$plugins = unserialize( $request['body']['plugins'] ); // todo use json now -- http://make.wordpress.org/core/2013/10/25/json-encoding-ssl-api-wordpress-3-7/
```
without disallowing unneeded classes.
thus, if attacker managed to control the value of $request['body']['plugins'] he will be able to:
1\. conduct PHP POP exploitation, more information:
http://www.slideshare.net/_s_n_t/php-unserialization-vulnerabilities-what-are-we-missing
http://www.slideshare.net/MailRuGroup/security-meetup-22-php-unserialize-exploiting
2\. unserialize itself has many security bugs in previous PHP versions which can be exploited, more information:
https://www.evonide.com/fuzzing-unserialize/
https://blog.checkpoint.com/wp-content/uploads/2016/08/Exploiting-PHP-7-unserialize-Report-160829.pdf
fix:
1\. don't use serialize/unserialize if json_encode/json_decode can be used instead. (fix both 1 & 2 attack vectors)
2\. if 1 isn't possible, use safe unserialize invocation, such as:
```
if (version_compare(PHP_VERSION, '7.0', 'lt')) {
return safeUnserialize($data);
} else {
return safeUnserialize($data, false);
}
```
Implement safeUnserialize function that based on PMA_safeUnserialize:
https://github.com/phpmyadmin/phpmyadmin/blob/fb161a7bebe60d902f743227158eca6a9889c472/libraries/core.lib.php#L1080
but with fix for the issue described in:
https://hackerone.com/reports/181315#activity-1322058
Report Details
Additional information and metadata
State
Closed
Substate
Resolved
Bounty
$25.00