A cybersecurity analyst is reviewing the logs of a proxy server and saw the following URLs:

https:$//$test$.$diontraining.com$/$profile$.$php$?$userid$=1546$

https:$//$test$.$diontraining.com$/$profile$.$php$?$userid$=5482$

https:$//$test$.$diontraining.com$/$profile$.$php$?$userid$=3618$

What type of vulnerability does this website have?

Insecure direct object reference $--$ correct answer.

Race condition

Improper error handling

Weak or default configurations

$----$

Can you explain why this is the correct answer?