vBulletin <= 5.6.9: Pre-authentication Remote Code Execution

Shodan dork: tag.vbulletin.version:<=5.6.9

https://github.com/ambionics/phpggc/blob/master/gadgetchains/vBulletin/RCE/1/chain.php

Exploitation steps:
https://www.ambionics.io/blog/vbulletin-unserializable-but-unreachable