Chamilo LMS: Database-backed PHP object injection in career deserialization

Chamilo LMS is an open-source learning management system. Prior to 2.0.1, `public/main/inc/lib/career.lib.php` and `public/main/cron/import_csv.php` call PHP's native `unserialize()` on `user_career.extra_data` retrieved from the database without the `allowed_classes: false` safety option. An attacker able to write crafted serialized PHP objects to that column, for example through a separate SQL injection, a compromised admin CSV import, or a lower-privilege admin panel, can instantiate arbitrary PHP objects and trigger POP gadget chains in autoloaded `Symfony`, `Doctrine`, or `Monolog` components. This permits arbitrary OS commands as the web server user, compromising server confidentiality, integrity, and availability. This issue is fixed in version 2.0.1.